485BPOS
Vanguard Extended Duration Treasury ETF
Prospectus
December 17, 2021
Exchange-traded fund shares that are not individually redeemable and are listed on NYSE Arca
Vanguard Extended Duration Treasury Index Fund ETF Shares (EDV)

This prospectus contains financial data for the Fund through the fiscal year ended August 31, 2021.

The Securities and Exchange Commission (SEC) has not approved or disapproved these securities or passed upon the adequacy of this prospectus. Any representation to the contrary is
a criminal offense.

Contents

ETF Summary
Investment Objective
The Fund seeks to track the performance of an index of extended-duration zero-coupon U.S. Treasury securities.
Fees and Expenses
The following table describes the fees and expenses you may pay if you buy, hold, and sell ETF Shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and example below.
Shareholder Fees
(Fees paid directly from your investment)
 
Transaction Fee on Purchases and Sales
None*
Transaction Fee on Reinvested Dividends
None*
Transaction Fee on Conversion to ETF Shares
None*
*
None through Vanguard (Broker fees vary)
Annual Fund Operating Expenses
(Expenses that you pay each year as a percentage of the value of your investment)
 
Management Fees
0.05%
12b-1 Distribution Fee
None
Other Expenses
0.01%
Total Annual Fund Operating Expenses
0.06%
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Example
The following example is intended to help you compare the cost of investing in the Fund’s ETF Shares with the cost of investing in other funds. It illustrates the hypothetical expenses that you would incur over various periods if you were to invest $10,000 in the Fund's shares. This example assumes that the shares provide a return of 5% each year and that total annual fund operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you were to sell your shares at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
1 Year
3 Years
5 Years
10 Years
$6
$19
$34
$77
This example does not include the brokerage commissions that you may pay to buy and sell ETF Shares of the Fund.
Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense example, reduce the Fund's performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 23% of the average value of its portfolio.
Principal Investment Strategies
The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. Treasury STRIPS 20–30 Year Equal Par Bond Index. This Index includes zero-coupon U.S. Treasury securities (Treasury STRIPS), which are backed by the full faith and credit of the U.S. government, with maturities ranging from 20 to 30 years. A Treasury STRIP represents a single coupon payment, or a single principal payment, from a U.S. Treasury security that has been “stripped” into separately tradable components.


The Fund invests by sampling the Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Index in terms of key risk factors, including duration, cash flow, and other characteristics. All of the Fund’s investments will be selected through the sampling process and, under normal circumstances, at least 80% of the Fund’s assets will be invested in
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U.S. Treasury securities held in the Index. The Fund maintains a dollar-weighted average maturity consistent with that of the Index. As of August 31, 2021, the dollar-weighted average maturity of the Index was 24.9 years.
Principal Risks
An investment in the Fund could lose money over short or long periods of time. You should expect the Fund's share price and total return to fluctuate within a wide range. The Fund is subject to the following risks, which could affect the Fund's performance, and the level of risk may vary based on market conditions:
•  Interest rate risk, which is the chance that bond prices overall will decline because of rising interest rates. The prices of long-term bonds, such as those held by the Fund, are much more sensitive to interest rate changes than are the prices of short-term bonds. Interest rate risk is expected to be very high for the Fund because it invests primarily in zero-coupon long-term bonds, which have prices that are even more sensitive to interest rate changes than are coupon-bearing bonds of similar maturity. Because the Fund invests primarily in Treasury STRIPS with maturities ranging from 20 to 30 years, rising interest rates may cause the value of the Fund’s investments to decline significantly.
•  Index sampling risk, which is the chance that the securities selected for the Fund, in the aggregate, will not provide investment performance matching that of the Fund's target index. Index sampling risk for the Fund is expected to be low.
Because ETF Shares are traded on an exchange, they are subject to additional risks:
• The Fund’s ETF Shares are listed for trading on NYSE Arca and are bought and sold on the secondary market at market prices. Although it is expected that the market price of an ETF Share typically will approximate its net asset value (NAV), there may be times when the market price and the NAV differ significantly. Thus, you may pay more or less than NAV when you buy ETF Shares on the secondary market, and you may receive more or less than NAV when you sell those shares.
• Although the Fund’s ETF Shares are listed for trading on NYSE Arca, it is possible that an active trading market may not be maintained.
• Trading of the Fund’s ETF Shares may be halted by the activation of individual or marketwide trading halts (which halt trading for a specific period of time when the price of a particular security or overall market prices decline by a specified percentage). Trading of the Fund’s ETF Shares may also be halted if (1) the shares are delisted from NYSE Arca without first being listed on another exchange or (2) NYSE Arca officials determine that such action is appropriate in the interest of a fair and orderly market or for the protection of investors.
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An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Annual Total Returns
The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund‘s ETF Shares (based on NAV) has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the ETF Shares compare with those of the Fund's target index and another comparative index, which have investment characteristics similar to those of the Fund. Keep in mind that the Fund's past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.
Annual Total Returns — Vanguard Extended Duration Treasury Index Fund ETF Shares1

1 The year-to-date return as of the most recent calendar quarter, which ended on September 30, 2021, was -10.12%.
During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:
 
Total Return
Quarter
Highest
52.06%
September 30, 2011
Lowest
-16.96%
December 31, 2016
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Average Annual Total Returns for Periods Ended December 31, 2020
 
1 Year
5 Years
10 Years
Vanguard Extended Duration Treasury Index Fund
ETF Shares
 
 
 
Based on NAV
 
 
 
Return Before Taxes
24.22%
10.48%
11.28%
Return After Taxes on Distributions
22.09
8.87
9.52
Return After Taxes on Distributions and Sale of Fund Shares
14.88
7.57
8.43
Based on Market Price
 
 
 
Return Before Taxes
23.70
10.44
11.26
Bloomberg U.S. Treasury STRIPS 20-30 Year Equal Par
Bond Index
(reflects no deduction for fees, expenses, or taxes)
24.04%
10.42%
11.35%
Bloomberg U.S. Aggregate Bond Index
(reflects no deduction for fees, expenses, or taxes)
7.51
4.44
3.84
Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. Please note that after-tax returns are not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.
Investment Advisor
The Vanguard Group, Inc. (Vanguard)
Portfolio Manager
Joshua C. Barrickman, CFA, Principal of Vanguard and co-head of Vanguard’s Fixed Income Indexing Americas. He has managed the Fund since 2013.
Purchase and Sale of Fund Shares
ETF Shares may only be bought and sold in the secondary market through a brokerage firm. The price you pay or receive for ETF Shares will be the prevailing market price, which may be more (premium) or less (discount) than the NAV of the shares. The brokerage firm may charge you a commission to execute the transaction. Unless imposed by your brokerage firm, there is no minimum dollar amount you must invest and no minimum number of shares you must buy. ETF
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Shares of the Fund cannot be directly purchased from or redeemed with the Fund, except by certain authorized broker-dealers. These broker-dealers may purchase and redeem ETF Shares only in large blocks (Creation Units), typically in exchange for baskets of securities.


An investor may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase ETF Shares (bid) and the lowest price a seller is willing to accept for ETF Shares (ask) when buying or selling shares in the secondary market (bid-ask spread). Recent information, including information on the Fund's NAV, market price, premiums and discounts, and bid-ask spreads, is available online at vanguard.com.
Tax Information
The Fund’s distributions may be taxable as ordinary income or capital gain. If you are investing through a tax-advantaged account, such as an IRA or an employer-sponsored retirement or savings plan, special tax rules apply.
Payments to Financial Intermediaries
The Fund and its investment advisor do not pay financial intermediaries for sales of Fund shares.
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Investing in Vanguard ETF® Shares
What Are Vanguard ETF Shares?
Vanguard ETF Shares are an exchange-traded class of shares issued by certain Vanguard funds. ETF Shares represent an interest in the portfolio of stocks or bonds held by the issuing fund. This prospectus describes Vanguard Extended Duration Treasury ETF, a class of shares issued by Vanguard Extended Duration Treasury Index Fund. In addition to ETF Shares, the Fund offers two conventional (not exchange-traded) classes of shares. This prospectus, however, relates only to ETF Shares.
How Are Vanguard ETF Shares Different From Conventional Mutual Fund Shares?
Conventional mutual fund shares can be directly purchased from and redeemed with the issuing fund for cash at the net asset value (NAV), typically calculated once a day. ETF Shares, by contrast, cannot be purchased directly from or redeemed directly with the issuing fund by an individual investor. Rather, ETF Shares can only be purchased or redeemed directly from the issuing fund by certain authorized broker-dealers. These broker-dealers may purchase and redeem ETF Shares only in large blocks (Creation Units), usually in exchange for baskets of securities and not for cash (although some funds issue and redeem Creation Units in exchange for cash or a combination of cash and securities).
An organized secondary trading market is expected to exist for ETF Shares, unlike conventional mutual fund shares, because ETF Shares are listed for trading on a national securities exchange. Individual investors can purchase and sell ETF Shares on the secondary market through a broker. Secondary-market transactions occur not at NAV, but at market prices that are subject to change throughout the day based on the supply of and demand for ETF Shares, changes in the prices of the fund’s portfolio holdings, and other factors.
The market price of a fund's ETF Shares typically will differ somewhat from the NAV of those shares. The difference between market price and NAV is expected to be small most of the time, but in times of market disruption or extreme market volatility, the difference may become significant.
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How Do I Buy and Sell Vanguard ETF Shares?
ETF Shares of the Fund are listed for trading on NYSE Arca. You can buy and sell ETF Shares on the secondary market in the same way you buy and sell any other exchange-traded security—through a broker. Your broker may charge a commission to execute a transaction. You will also incur the cost of the “bid-ask spread,” which is the difference between the highest price a buyer is willing to pay to purchase ETF Shares (bid) and the lowest price a seller is willing to accept for ETF Shares (ask) when buying or selling shares in the secondary market. Because secondary-market transactions occur at market prices, you may pay more (premium) or less (discount) than NAV when you buy ETF Shares and receive more or less than NAV when you sell those shares. In times of severe market disruption, the bid-ask spread and premiums/discounts can increase significantly. Unless imposed by your broker, there is no minimum dollar amount you must invest and no minimum number of ETF Shares you must buy.
Your ownership of ETF Shares will be shown on the records of the broker through which you hold the shares. Vanguard will not have any record of your ownership. Your account information will be maintained by your broker, which will provide you with account statements, confirmations of your purchases and sales of ETF Shares, and tax information. Your broker also will be responsible for ensuring that you receive income and capital gains distributions, as well as shareholder reports and other communications from the fund whose ETF Shares you own. You will receive other services (e.g., dividend reinvestment and average cost information) only if your broker offers these services.
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Investing in Index Funds
What Is Indexing?
Indexing is an investment strategy for tracking the performance of a specified market benchmark, or “index.” An index is a group of securities whose overall performance is used as a standard to measure the investment performance of a particular market. There are many types of indexes. Some represent entire markets—such as the U.S. stock market or the U.S. bond market. Other indexes cover market segments—such as small-capitalization stocks or short-term bonds. One cannot invest directly in an index.
The index sponsor determines the securities to include in the index and the weighting of each security in the index. Under normal circumstances, the index sponsor will rebalance an index on a regular schedule. An index sponsor may carry out additional ad hoc index rebalances or delay or cancel a scheduled rebalance. Generally, the index sponsor does not provide any warranty, or accept any liability, with respect to the quality, accuracy, or completeness of either the target index or its related data. Errors made by the index sponsor may occur from time to time and may not be identified by the index sponsor for a period of time or at all. Vanguard does not provide any warranty or guarantee against such errors. Therefore, the gains, losses, or costs associated with the index sponsor’s errors will generally be borne by the index fund and its shareholders.
An index fund seeks to hold all, or a representative sample, of the securities that make up its target index. Index funds attempt to mirror the performance of the target index, for better or worse. However, an index fund generally does not perform exactly like its target index. For example, index funds have operating expenses and transaction costs. Market indexes do not, and therefore they will usually have a slight performance advantage over funds that track them. The ability of an index fund to match its performance to that of its target index can also be impacted by, among other things, the timing and size of cash flows and the size of the fund. Market disruptions and regulatory restrictions could also have an adverse effect on a fund’s ability to adjust its exposure to the required levels in order to track the index.
Index funds typically have the following characteristics:
•  Variety of investments. Depending on a fund’s benchmark index, the fund may invest in the securities of a variety of companies, industries, and/or governments or government agencies.
•  Relative performance consistency. Because they seek to track market benchmarks, index funds usually do not perform dramatically better or worse than their benchmarks.
•  Low cost. Index funds are generally inexpensive to run compared with actively managed funds. They have low or no research costs and typically keep trading activity—and thus dealer markups and other transaction costs—to a minimum compared with actively managed funds.
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More on the Fund and ETF Shares
This prospectus describes the principal risks you would face as a Fund shareholder. It is important to keep in mind one of the main principles of investing: generally, the higher the risk of losing money, the higher the potential reward. The reverse, also, is generally true: the lower the risk, the lower the potential reward. As you consider an investment in any fund, you should take into account your personal tolerance for fluctuations in the securities markets. Look for this   symbol throughout the prospectus. It is used to mark detailed information about the more significant risks that you would confront as a Fund shareholder. To highlight terms and concepts important to fund investors, we have provided Plain Talk® explanations along the way. Reading the prospectus will help you decide whether the Fund is the right investment for you. We suggest that you keep this prospectus for future reference.
Share Class Overview
This prospectus offers the Fund’s ETF Shares, an exchange-traded class of shares. A separate prospectus offers the Fund’s Institutional Shares and Institutional Plus Shares, which are generally for investors who invest a minimum of $5 million and $100 million, respectively.
All share classes offered by the Fund have the same investment objective, strategies, and policies. However, different share classes have different expenses; as a result, their investment returns will differ.
A Note to Investors
Vanguard ETF Shares can be purchased directly from the issuing Fund only by certain authorized broker-dealers in exchange for a basket of securities (or, in some cases, for cash or a combination of cash and securities). Individual investors generally will not be able to purchase ETF Shares directly from the Fund. Instead, these investors will purchase ETF Shares on the secondary market through a broker.
The Fund is primarily intended for pension plans and other institutional investors that desire to closely match long-term liabilities with a portfolio of U.S. Treasury securities of similar long-term duration. Interest rate risk is expected to be extremely high for the Fund because it invests primarily in zero-coupon long-term bonds, which have prices that are even more sensitive to interest rate changes than are coupon-bearing bonds of similar maturity. Because the Fund invests primarily in Treasury STRIPS with maturities ranging from 20 to 30 years, rising interest rates may cause the value of the Fund’s investments to decline significantly. Prospective investors are urged to consult with their own advisors to determine the suitability of an investment in the Fund and the relationship of such an investment to their overall investment program and financial and tax positions.
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Plain Talk About Fund Expenses
All funds have operating expenses. These expenses, which are deducted
from a fund’s gross income, are expressed as a percentage of the net assets
of the fund. Assuming that operating expenses remain as stated in the Fees
and Expenses section, Vanguard Extended Duration Treasury Index Fund ETF
Shares’ expense ratio would be 0.06%, or $0.60 per $1,000 of average net
assets. The average expense ratio for general U.S. Treasury funds in 2020
was 0.23%, or $2.30 per $1,000 of average net assets (derived from data
provided by Lipper, a Thomson Reuters Company, which reports on the
fund industry).
Plain Talk About Costs of Investing
Costs are an important consideration in choosing an ETF. That is because
you, as a shareholder, pay a proportionate share of the costs of operating a
fund and any transaction costs incurred when the fund buys or sells
securities. These costs can erode a substantial portion of the gross income
or the capital appreciation a fund achieves. Even seemingly small differences
in expenses can, over time, have a dramatic effect on a fund’s performance.
The following sections explain the principal investment strategies and policies that the Fund uses in pursuit of its investment objective. The Fund's board of trustees, which oversees the Fund's management, may change investment strategies or policies in the interest of shareholders without a shareholder vote, unless those strategies or policies are designated as fundamental. Note that the Fund’s investment objective is not fundamental and may be changed without a shareholder vote. The Fund may change its policy of investing at least 80% of its assets in U.S. Treasury securities that are part of the target index only upon 60 days’ notice to shareholders.
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Market Exposure
Plain Talk About Treasury STRIPS
A Treasury STRIP represents a single coupon payment, or a single principal
payment, on a U.S. Treasury security that has been “stripped” into separately
tradable components. For example, a newly issued 10-year U.S. Treasury
note can be divided into 20 semiannual coupon payments (coupon STRIPS)
and a single principal payment (principal STRIP). Treasury STRIPS are
obligations of the U.S. Treasury and are backed by the full faith and credit of
the U.S. government.
Treasury STRIPS are sometimes called zero-coupon securities because the
only time an investor receives payment is at maturity. Consequently, these
securities are more sensitive to changes in interest rates than
coupon-bearing securities with the same maturity date. Treasury STRIPS
are popular with pension funds and insurance companies because these
securities have known cash values at maturity, which enables investors to
closely match their liabilities with guaranteed payments from the
U.S. Treasury. Because Treasury STRIPS do not pay interest, they are issued
and sold at a discount to face value.
We expect the Fund will be required to distribute income dividends to
shareholders, but because Treasury STRIPS do not pay interest and are
purchased at an “original issue discount,” the Fund does not receive cash
interest payments on the STRIPS in which it invests. As a result, the Fund
may need to liquidate assets, at potentially inopportune times, to satisfy its
income dividend distribution requirements.
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The Fund is subject to interest rate risk, which is the chance that bond prices overall will decline because of rising interest rates. The prices of long-term bonds, such as those held by the Fund, are much more sensitive to interest rate changes than are the prices of short-term bonds. Interest rate risk is expected to be very high for the Fund because it invests primarily in zero-coupon long-term bonds, which have prices that are even more sensitive to interest rate changes than are coupon-bearing bonds of similar maturity. Because the Fund invests primarily in Treasury STRIPS with maturities ranging from 20 to 30 years, rising interest rates may cause the value of the Fund’s investments to decline significantly.
Although fixed income securities (commonly referred to as bonds) are often thought to be less risky than stocks, there have been periods when bond prices have fallen significantly because of rising interest rates. For instance, prices of long-term bonds fell by almost 48% between December 1976 and September 1981.
To illustrate the relationship between bond prices and interest rates, the following table shows the effect of a 1% and a 2% change (both up and down) in interest rates on the values of four noncallable bonds (i.e., bonds that cannot be redeemed by the issuer) of different maturities, each with a face value of $1,000.
How Interest Rate Changes Affect the Value of a $1,000 Bond
Type of Bond (Maturity)
After a 1%
Increase
After a 1%
Decrease
After a 2%
Increase
After a 2%
Decrease
Short-Term (2.5 years)1
$ 977
$ 1,024
$ 954
$ 1,049
Intermediate-Term (10 years)1
922
1,086
851
1,180
Long-Term (20 years)1
874
1,150
769
1,328
Long-Term Zero-Coupon (20 years)
800
1,200
600
1,400
1 Assuming a 4% coupon rate.
These figures are for illustration only; you should not regard them as an indication of future performance of the bond market as a whole or the Fund in particular.
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Plain Talk About Bonds and Interest Rates
As a rule, when interest rates rise, bond prices fall. The opposite is also true:
Bond prices go up when interest rates fall. Why do bond prices and interest
rates move in opposite directions? Let’s assume that you hold a bond
offering a 4% yield. A year later, interest rates are on the rise and bonds of
comparable quality and maturity are offered with a 5% yield. With
higher-yielding bonds available, you would have trouble selling your 4% bond
for the price you paid—you would probably have to lower your asking price.
On the other hand, if interest rates were falling and 3% bonds were being
offered, you should be able to sell your 4% bond for more than you paid.
Changes in interest rates can affect bond income as well as bond prices.
Plain Talk About Bond Maturities
A bond is issued with a specific maturity date—the date when the issuer
must pay back the bond’s principal (face value). Bond maturities range from
less than 1 year to more than 30 years. Typically, the longer a bond’s maturity,
the more price risk you, as a bond investor, will face as interest rates
rise—but also the higher the potential yield you could receive. Longer-term
bonds are generally more suitable for investors willing to take a greater risk
of price fluctuations to get higher and more stable interest income.
Shorter-term bond investors should be willing to accept lower yields and
greater income variability in return for less fluctuation in the value of their
investment. The stated maturity of a bond may differ from the effective
maturity of a bond, which takes into consideration that an action such as a
call or refunding may cause bonds to be repaid before their stated
maturity dates.
Market disruptions can adversely affect local and global markets as well as normal market conditions and operations. Any such disruptions could have an adverse impact on the value of the Fund's investments and Fund performance.
Security Selection
Index sampling strategy. The Fund uses index “sampling” techniques to select securities. Using computer programs, the Fund’s advisor generally selects a representative sample of securities that approximates the full target index in terms of key risk factors—such as duration and cash flow—and other
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characteristics. Because the Fund does not hold all of the securities in its target index, some of the securities that are held will likely be overweighted (or underweighted) compared with the target index.
The Fund is subject to index sampling risk, which is the chance that the securities selected for the Fund, in the aggregate, will not provide investment performance matching that of the Fund's target index. Index sampling risk for the Fund is expected to be low.
Types of bonds. The Fund’s target index is the Bloomberg U.S. Treasury STRIPS 20–30 Year Equal Par Bond Index. This Index includes Treasury STRIPS with maturities ranging from 20 to 30 years. The number of bonds held by the Fund and the number of bonds in the Fund’s target index were 80 and 80, respectively, as of August 31, 2021.
Other Investment Policies and Risks
The Fund reserves the right to substitute a different index for the index it currently tracks if the current index is discontinued, if the Fund's agreement with the sponsor of its target index is terminated, or for any other reason determined in good faith by the Fund’s board of trustees. In any such instance, the substitute index would represent the same market segment as the current index.
The Fund may invest, to a limited extent, in derivatives. Generally speaking, a derivative is a financial contract whose value is based on the value of a financial asset (such as a stock, a bond, or a currency), a physical asset (such as gold, oil, or wheat), a market index, or a reference rate. Investments in derivatives may subject the Fund to risks different from, and possibly greater than, those of investments directly in the underlying securities or assets. The Fund will not use derivatives for speculation or for the purpose of leveraging (magnifying) investment returns.
The Fund may invest a small portion of its assets in fixed income futures, which are a type of derivative, and/or shares of exchange-traded funds (ETFs). These fixed income futures and ETFs typically provide returns similar to those of the bonds listed in the index, or in a subset of the index, the Fund seeks to track. The Fund may purchase futures or ETFs when doing so will reduce the Fund’s transaction costs, facilitate cash management, mitigate risk, or have the potential to add value because the instruments are favorably priced. Vanguard receives no additional revenue from Fund assets invested in ETF Shares of other Vanguard funds. Fund assets invested in ETF Shares are excluded when allocating to the Fund its share of the costs of Vanguard operations.
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Cash Management
The Fund's daily cash balance may be invested in Vanguard Market Liquidity Fund and/or Vanguard Municipal Cash Management Fund (each, a CMT Fund), which are low-cost money market funds. When investing in a CMT Fund, the Fund bears its proportionate share of the expenses of the CMT Fund in which it invests. Vanguard receives no additional revenue from Fund assets invested in a CMT Fund.
Methods Used to Meet Redemption Requests
Redemptions of ETF Shares are typically met through a combination of cash and securities held by the Fund; see “How Are Vanguard ETF Shares Different From Conventional Mutual Fund Shares?” If cash is used to meet redemptions, the Fund typically obtains such cash through positive cash flows or the sale of Fund holdings consistent with the Fund’s investment objective and strategy. Please consult the Fund's Statement of Additional Information for further information on redemptions of ETF Shares.
Under certain circumstances, the Fund may borrow money (subject to certain regulatory conditions and if available under board-approved procedures) through an interfund lending facility; through a bank line-of-credit, including a joint committed credit facility; or through an uncommitted line-of-credit from Vanguard in order to meet redemption requests.
Temporary Investment Measures
The Fund may temporarily depart from its normal investment policies and strategies when the advisor believes that doing so is in the Fund's best interest, so long as the strategy or policy employed is consistent with the Fund's investment objective. For instance, the Fund may invest beyond its normal limits in derivatives or exchange-traded funds that are consistent with the Fund's investment objective when those instruments are more favorably priced or provide needed liquidity, as might be the case when the Fund receives large cash flows that it cannot prudently invest immediately.
Special Risks of Exchange-Traded Shares
ETF Shares are not individually redeemable. They can be redeemed with the issuing Fund at NAV only by certain authorized broker-dealers and only in large blocks known as Creation Units. Consequently, if you want to liquidate some or all of your ETF Shares, you must sell them on the secondary market at prevailing market prices.
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The market price of ETF Shares may differ from NAV. Although it is expected that the market price of an ETF Share typically will approximate its NAV, there may be times when the market price and the NAV differ significantly. Thus, you may pay more (premium) or less (discount) than NAV when you buy ETF Shares on the secondary market, and you may receive more or less than NAV when you sell those shares. These discounts and premiums are likely to be greatest during times of market disruption or extreme market volatility.
Vanguard’s website at vanguard.com shows the previous day’s closing NAV and closing market price for the Fund's ETF Shares. The website also discloses, in the Premium/Discount Analysis section of the ETF Shares’ Price & Performance page, how frequently the Fund’s ETF Shares traded at a premium or discount to NAV (based on closing NAVs and market prices) and the magnitudes of such premiums and discounts.
An active trading market may not exist. Although Vanguard ETF Shares are listed on a national securities exchange, it is possible that an active trading market may not be maintained. Although this could happen at any time, it is more likely to occur during times of severe market disruption. If you attempt to sell your ETF Shares when an active trading market is not functioning, you may have to sell at a significant discount to NAV. In extreme cases, you may not be able to sell your shares at all.
Trading may be halted. Trading of Vanguard ETF Shares on an exchange may be halted by the activation of individual or marketwide trading halts (which halt trading for a specific period of time when the price of a particular security or overall market prices decline by a specified percentage). Trading of ETF Shares may also be halted if (1) the shares are delisted from the listing exchange without first being listed on another exchange or (2) exchange officials determine that such action is appropriate in the interest of a fair and orderly market or for the protection of investors.
Conversion Privilege
Owners of conventional shares issued by the Fund may convert those shares to ETF Shares of equivalent value of the same fund. Please note that investors who own conventional shares through a 401(k) plan or other employer-sponsored retirement or benefit plan generally may not convert those shares to ETF Shares and should check with their plan sponsor or recordkeeper. ETF Shares, whether acquired through a conversion or purchased on the secondary market, cannot be converted to conventional shares by a shareholder. Also, ETF Shares of one fund cannot be exchanged for ETF Shares of another fund.
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You must hold ETF Shares in a brokerage account. Thus, before converting conventional shares to ETF Shares, you must have an existing, or open a new, brokerage account. This account may be with Vanguard Brokerage Services® or with any other brokerage firm. To initiate a conversion of conventional shares to ETF Shares, please contact your broker.
Vanguard Brokerage Services does not impose a fee on conversions from Vanguard conventional shares to Vanguard ETF Shares. However, other brokerage firms may charge a fee to process a conversion. Vanguard reserves the right, in the future, to impose a transaction fee on conversions or to limit, temporarily suspend, or terminate the conversion privilege.
Converting conventional shares to ETF Shares is generally accomplished as follows. First, after your broker notifies Vanguard of your request to convert, Vanguard will transfer your conventional shares from your account to the broker’s omnibus account with Vanguard (an account maintained by the broker on behalf of all its customers who hold conventional Vanguard fund shares through the broker). After the transfer, Vanguard’s records will reflect your broker, not you, as the owner of the shares. Next, your broker will instruct Vanguard to convert the appropriate number or dollar amount of conventional shares in its omnibus account to ETF Shares of equivalent value, based on the respective NAVs of the two share classes.
Your Fund’s transfer agent will reflect ownership of all ETF Shares in the name of the Depository Trust Company (DTC). The DTC will keep track of which ETF Shares belong to your broker, and your broker, in turn, will keep track of which ETF Shares belong to you.
Because the DTC is unable to handle fractional shares, only whole shares can be converted. For example, if you owned 300.25 conventional shares, and this was equivalent in value to 90.75 ETF Shares, the DTC account would receive 90 ETF Shares. Conventional shares with a value equal to 0.75 ETF Shares (in this example, that would be 2.481 conventional shares) would remain in the broker’s omnibus account with Vanguard. Your broker then could either (1) credit your account with 0.75 ETF Shares or (2) redeem the 2.481 conventional shares for cash at NAV and deliver that cash to your account. If your broker chose to redeem your conventional shares, you would realize a gain or loss on the redemption that must be reported on your tax return (unless you hold the shares in an IRA or other tax-deferred account). Please consult your broker for information on how it will handle the conversion process, including whether it will impose a fee to process a conversion.
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If you convert your conventional shares to ETF Shares through Vanguard Brokerage Services, all conventional shares for which you request conversion will be converted to ETF Shares of equivalent value. Because no fractional shares will have to be sold, the transaction will not be taxable.
Here are some important points to keep in mind when converting conventional shares of a Vanguard fund to ETF Shares:
• The conversion process can take anywhere from several days to several weeks, depending on your broker. Vanguard generally will process conversion requests either on the day they are received or on the next business day. Vanguard imposes conversion blackout windows around the dates when a fund with ETF Shares declares dividends. This is necessary to prevent a shareholder from collecting a dividend from both the conventional share class currently held and also from the ETF share class to which the shares will be converted.
• Until the conversion process is complete, you will remain fully invested in a fund’s conventional shares, and your investment will increase or decrease in value in tandem with the NAV of those shares.
• The conversion transaction is nontaxable except, if applicable, to the very limited extent previously described.
A precautionary note to investment companies: Vanguard ETF Shares are issued by registered investment companies, and therefore the acquisition of such shares by other investment companies is subject to the restrictions of Section 12(d)(1) of the Investment Company Act of 1940. Vanguard has obtained SEC exemptive orders that allow registered investment companies to invest in the issuing funds beyond the limits of Section 12(d)(1), subject to certain terms and conditions, including the requirement to enter into a participation agreement with Vanguard. The SEC recently adopted changes to the regulatory framework for fund of funds arrangements, and, as a result, Vanguard's exemptive orders will be rescinded by the SEC on January 19, 2022. However, effective January 19, 2022, new Rule 12d1-4 under the Investment Company Act of 1940 permits registered investment companies to invest in other registered investment companies beyond the limits in Section 12(d)(1), subject to certain conditions, including that the funds enter into a fund of funds investment agreement.
Shareholder Rights
The Fund's Agreement and Declaration of Trust, as amended, requires a shareholder bringing a derivative action on behalf of the Trust that is subject to a pre-suit demand to collectively hold at least 10% of the outstanding shares of the Trust or at least 10% of the outstanding shares of the series or class to which the demand relates and to undertake to reimburse the Trust for the
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expense of any counsel or advisors used when considering the merits of the demand in the event that the Trustees determine not to bring such action. In each case, these requirements do not apply to claims arising under the federal securities laws to the extent that any such federal securities laws, rules, or regulations do not permit such application.
Frequent Trading and Market-Timing
Unlike frequent trading of a Vanguard fund’s conventional (i.e., not exchange-traded) classes of shares, frequent trading of ETF Shares does not disrupt portfolio management or otherwise harm fund shareholders. The vast majority of trading in ETF Shares occurs on the secondary market. Because these trades do not involve the issuing fund, they do not harm the fund or its shareholders. Certain broker-dealers are authorized to purchase and redeem ETF Shares directly with the issuing fund. Because these trades typically are effected in kind (i.e., for securities and not for cash), or are assessed a transaction fee when effected in cash, they do not cause any of the harmful effects to the issuing fund (as previously noted) that may result from frequent trading. For these reasons, the board of trustees of each fund that issues ETF Shares has determined that it is not necessary to adopt policies and procedures to detect and deter frequent trading and market-timing of ETF Shares.
Portfolio Holdings
Please consult the Fund's Statement of Additional Information or our website for a description of the policies and procedures that govern disclosure of the Fund’s portfolio holdings.
Turnover Rate
Although the Fund generally seeks to invest for the long term, it may sell securities regardless of how long they have been held. Generally, an index fund sells securities in response to redemption requests from shareholders of conventional (not exchange-traded) shares or to changes in the composition of its target index. The Fund may also sell securities in an effort to manage its duration. The Financial Highlights section of this prospectus shows historical turnover rates for the Fund. A turnover rate of 100%, for example, would mean that the Fund had sold and replaced securities valued at 100% of its net assets within a one-year period. In general, the greater the turnover rate, the greater the impact transaction costs will have on a fund’s return. Also, funds with high turnover rates may be more likely to generate capital gains, including short-term capital gains, that must be distributed to shareholders and will be taxable to shareholders investing through a taxable account.
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The Fund and Vanguard
The Fund is a member of The Vanguard Group, a family of over 200 funds. All of the funds that are members of The Vanguard Group (other than funds of funds) share in the expenses associated with administrative services and business operations, such as personnel, office space, and equipment.
Vanguard Marketing Corporation provides marketing services to the funds. Although fund shareholders do not pay sales commissions or 12b-1 distribution fees, each fund (other than a fund of funds) or each share class of a fund (in the case of a fund with multiple share classes) pays its allocated share of the Vanguard funds’ marketing costs.
Plain Talk About Vanguard’s Unique Corporate Structure
The Vanguard Group is owned jointly by the funds it oversees and thus
indirectly by the shareholders in those funds. Most other mutual funds are
operated by management companies that are owned by third parties—either
public or private stockholders—and not by the funds they serve.
Investment Advisor
The Vanguard Group, Inc., P.O. Box 2600, Valley Forge, PA 19482, which began operations in 1975, serves as advisor to the Fund through its Fixed Income Group. As of August 31, 2021, Vanguard served as advisor for approximately $6.7 trillion in assets. Vanguard provides investment advisory services to the Fund pursuant to the Funds’ Service Agreement and subject to the supervision and oversight of the trustees and officers of the Fund.
For the fiscal year ended August 31, 2021, the advisory expenses represented an effective annual rate of less than 0.01% of the Fund’s average net assets.
For a discussion of why the board of trustees approved the Fund's investment advisory arrangement, see the most recent annual report to shareholders covering the fiscal year ended August 31.
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The manager primarily responsible for the day-to-day management of the Fund is:
Joshua C. Barrickman, CFA, Principal of Vanguard and co-head of Vanguard’s Fixed Income Indexing Americas. He has been with Vanguard since 1998, has worked in investment management since 1999, has managed investment portfolios since 2005, and has managed the Fund since 2013. Education: B.S., Ohio Northern University; M.B.A., Lehigh University.
The Fund's Statement of Additional Information provides information about the portfolio manager’s compensation, other accounts under management, and ownership of shares of the Fund.
Dividends, Capital Gains, and Taxes
Fund Distributions
The Fund distributes to shareholders virtually all of its net income (interest less expenses) as well as any net short-term or long-term capital gains realized from the sale of its holdings. From time to time, the Fund may also make distributions that are treated as a return of capital. Income dividends are generally declared and distributed quarterly in March, June, September, and December; capital gains distributions, if any, generally occur annually in December. In addition, the Fund may occasionally make a supplemental distribution at some other time during the year. Because of the “original issue discount” on zero-coupon securities, we expect the Fund will be required to distribute income dividends to shareholders, although the Fund does not receive cash interest payments on the STRIPS in which it invests.
Plain Talk About Distributions
As a shareholder, you are entitled to your portion of a fund’s income from
interest as well as capital gains from the fund’s sale of investments. Income
consists of interest the fund earns from its money market and bond
investments. Capital gains are realized whenever the fund sells securities for
higher prices than it paid for them. These capital gains are either short-term
or long-term, depending on whether the fund held the securities for one year
or less or for more than one year.
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Reinvestment of Distributions
In order to reinvest dividend and capital gains distributions, investors in the Fund's ETF Shares must hold their shares at a broker that offers a reinvestment service. This can be the broker’s own service or a service made available by a third party, such as the broker’s outside clearing firm or the DTC. If a reinvestment service is available, distributions of income and capital gains can automatically be reinvested in additional whole and fractional ETF Shares of the Fund. If a reinvestment service is not available, investors will receive their distributions in cash. To determine whether a reinvestment service is available and whether there is a commission or other charge for using this service, consult your broker.
As with all exchange-traded funds, reinvestment of dividend and capital gains distributions in additional ETF Shares will occur four business days or more after the ex-dividend date (the date when a distribution of dividends or capital gains is deducted from the price of the Fund’s shares). The exact number of days depends on your broker. During that time, the amount of your distribution will not be invested in the Fund and therefore will not share in the Fund’s income, gains, and losses.
Basic Tax Points
Investors in taxable accounts should be aware of the following basic federal income tax points:
• Distributions are taxable to you whether or not you reinvest these amounts in additional ETF Shares.
• “Original issue discount” on a Treasury STRIP is generally treated as interest, although the Fund does not receive cash interest payments on the STRIPS in which it invests.
• Distributions declared in December—if paid to you by the end of January—are taxable as if received in December.
• Any income dividend distribution or short-term capital gains distribution that you receive is taxable to you as ordinary income.
• Any distribution of net long-term capital gains is taxable to you as long-term capital gains, no matter how long you have owned ETF Shares.
• Capital gains distributions may vary considerably from year to year as a result of the Fund's normal investment activities and cash flows.
• Your cost basis in the Fund will be decreased by the amount of any return of capital that you receive. This, in turn, will affect the amount of any capital gain or loss that you realize when selling your ETF Shares.
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• Return of capital distributions generally are not taxable to you until your cost basis has been reduced to zero. If your cost basis is at zero, return of capital distributions will be treated as capital gains.
• A sale of ETF Shares is a taxable event. This means that you may have a capital gain to report as income, or a capital loss to report as a deduction, when you complete your tax return.
Individuals, trusts, and estates whose income exceeds certain threshold amounts are subject to a 3.8% Medicare contribution tax on “net investment income.” Net investment income takes into account distributions paid by the Fund and capital gains from any sale of ETF Shares.
Income dividends and capital gains distributions that you receive, as well as your gains or losses from any sale of ETF Shares, may be subject to state and local income taxes. Depending on your state’s rules, however, any dividends attributable to interest earned on direct obligations of the U.S. government may be exempt from state and local taxes. Vanguard will notify you each year how much, if any, of your dividends may qualify for this exemption.
This prospectus provides general tax information only. If you are investing through a tax-advantaged account, such as an IRA or an employer-sponsored retirement or savings plan, special tax rules apply. Please consult your tax advisor for detailed information about any tax consequences for you.
Share Price and Market Price
Share price, also known as net asset value (NAV), is calculated as of the close of regular trading on the New York Stock Exchange (NYSE), generally 4 p.m., Eastern time, on each day that the NYSE is open for business (a business day). In the rare event the NYSE experiences unanticipated disruptions and is unavailable at the close of the trading day, NAVs will be calculated as of the close of regular trading on the Nasdaq (or another alternate exchange if the Nasdaq is unavailable, as determined at Vanguard’s discretion), generally 4 p.m., Eastern time. Each share class has its own NAV, which is computed by dividing the total assets, minus liabilities, allocated to the share class by the number of Fund shares outstanding for that class. On U.S. holidays or other days when the NYSE is closed, the NAV is not calculated, and the Fund does not sell or redeem shares.
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Remember: If you buy or sell ETF Shares on the secondary market, you will pay or receive the market price, which may be higher or lower than NAV. Your transaction will be priced at NAV only if you purchase or redeem your ETF Shares in Creation Unit blocks (an option available only to certain authorized broker-dealers) or if you convert your conventional fund shares to ETF Shares.
Debt securities held by a Vanguard fund are valued based on information furnished by an independent pricing service or market quotations. When a fund determines that pricing-service information or market quotations either are not readily available or do not accurately reflect the value of a security, the security is priced at its fair value (the amount that the owner might reasonably expect to receive upon the current sale of the security).
The values of any foreign securities held by a fund are converted into U.S. dollars using an exchange rate obtained from an independent third party as of the close of regular trading on the NYSE. The values of any mutual fund shares, including institutional money market fund shares, held by a fund are based on the NAVs of the shares. The values of any ETF shares or closed-end fund shares held by a fund are based on the market value of the shares.
A fund also may use fair-value pricing on bond market holidays when the fund is open for business (such as Columbus Day and Veterans Day). Fair-value prices are determined by Vanguard according to procedures adopted by the board of trustees. When fair-value pricing is employed, the prices of securities used by a fund to calculate the NAV may differ from quoted or published prices for the same securities.
Vanguard’s website will show the previous day’s closing NAV and closing market price for the Fund’s ETF Shares.
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Additional Information
The Fund’s Bylaws require, unless the Trust otherwise consents in writing, that the U.S. Federal District Courts be the sole and exclusive forum for the resolution of complaints under the Securities Act of 1933. This provision may limit a shareholder’s ability to bring a claim in a different forum and may result in increased shareholder costs in pursuing such a claim.
 
Inception Date
Vanguard
Fund Number
CUSIP
Number
Extended Duration Treasury Index Fund
ETF Shares
12/6/2007
930
921910709
Certain affiliates of the Fund and the advisor may purchase and resell ETF Shares pursuant to the prospectus.


CGS identifiers have been provided by CUSIP Global Services, managed on behalf of the American Bankers Association by Standard & Poor’s Financial Services, LLC, and are not for use or dissemination in a manner that would serve as a substitute for any CUSIP service. The CUSIP Database, ©2021 American Bankers Association. “CUSIP” is a registered trademark of the American Bankers Association.
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Financial Highlights
Financial highlights information is intended to help you understand a fund’s performance for the past five years (or, if shorter, its period of operations). Certain information reflects financial results for a single fund share. Total return represents the rate that an investor would have earned or lost each period on an investment in a fund or share class (assuming reinvestment of all distributions). This information has been obtained from the financial statements audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, whose report, along with fund financial statements, is included in a fund’s most recent annual report to shareholders. You may obtain a free copy of a fund’s latest annual or semiannual report, which is available upon request.
Vanguard Extended Duration Treasury Index Fund ETF Shares
 
Year Ended August 31,
For a Share Outstanding Throughout Each Period
2021
2020
2019
2018
2017
Net Asset Value, Beginning of Period
$163.11
$146.43
$113.39
$120.92
$139.77
Investment Operations
 
 
 
 
 
Net Investment Income1
2.795
3.146
3.347
3.353
3.383
Net Realized and Unrealized Gain (Loss) on
Investments2
(17.061)
18.113
32.972
(7.272)
(16.377)
Total from Investment Operations
(14.266)
21.259
36.319
(3.919)
(12.994)
Distributions
 
 
 
 
 
Dividends from Net Investment Income
(2.820)
(3.329)
(3.279)
(3.314)
(3.402)
Distributions from Realized Capital Gains
(5.334)
(1.250)
(.297)
(2.454)
Total Distributions
(8.154)
(4.579)
(3.279)
(3.611)
(5.856)
Net Asset Value, End of Period
$140.69
$163.11
$146.43
$113.39
$120.92
Total Return
-8.94%
14.98%
32.92%
-3.24%
-8.86%
Ratios/Supplemental Data
 
 
 
 
 
Net Assets, End of Period (Millions)
$1,277
$1,810
$1,333
$658
$623
Ratio of Total Expenses to Average Net Assets
0.06%
0.07%
0.07%
0.07%
0.07%
Ratio of Net Investment Income to Average Net
Assets
1.93%
2.06%
2.87%
2.93%
2.90%
Portfolio Turnover Rate3
23%
17%
20%
18%
18%
 
 
1
Calculated based on average shares outstanding.
2
Includes increases from purchase fees of $.07, $.07, $.04, $.07, and $.16.
3
Excludes the value of portfolio securities received or delivered as a result of in-kind purchases or redemptions of
the fund’s capital shares, including ETF Creation Units.
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CFA® is a registered trademark owned by CFA Institute.
Bloomberg®” and the Bloomberg U.S. Treasury STRIPS 20-30 Year Equal Par Bond Index and Bloomberg U.S. Aggregate Bond Index (the Indices or Bloomberg Indices) are service marks of Bloomberg Finance L.P. and its affiliates, including Bloomberg Index Services Limited (“BISL”), the administrator of the Indices (collectively, “Bloomberg”), and have been licensed for use for certain purposes by Vanguard.
The Extended Duration Treasury ETF is not sponsored, endorsed, sold or promoted by Bloomberg. Bloomberg does not make any representation or warranty, express or implied, to the owners of or counterparties to the Extended Duration Treasury ETF or any member of the public regarding the advisability of investing in securities generally or in the Extended Duration Treasury ETF particularly. The only relationship of Bloomberg to Vanguard is the licensing of certain trademarks, trade names and service marks and of the Bloomberg U.S. Treasury STRIPS 20-30 Year Equal Par Bond Index and Bloomberg U.S. Aggregate Bond Index, which is determined, composed and calculated by BISL without regard to Vanguard or the Extended Duration Treasury ETF. Bloomberg has no obligation to take the needs of Vanguard or the owners of the Extended Duration Treasury ETF into consideration in determining, composing or calculating the Bloomberg U.S. Treasury STRIPS 20-30 Year Equal Par Bond Index and Bloomberg U.S. Aggregate Bond Index. Bloomberg is not responsible for and has not participated in the determination of the timing of, prices at, or quantities of the Extended Duration Treasury ETF to be issued. Bloomberg shall not have any obligation or liability, including, without limitation, to the Extended Duration Treasury ETF customers, in connection with the administration, marketing or trading of the Extended Duration Treasury ETF.
BLOOMBERG DOES NOT GUARANTEE THE ACCURACY AND/OR THE COMPLETENESS OF THE BLOOMBERG INDICES OR ANY DATA RELATED THERETO AND SHALL HAVE NO LIABILITY FOR ANY ERRORS, OMISSIONS OR INTERRUPTIONS THEREIN. BLOOMBERG DOES NOT MAKE ANY WARRANTY, EXPRESS OR IMPLIED, AS TO RESULTS TO BE OBTAINED BY VANGUARD, OWNERS OF THE EXTENDED DURATION TREASURY ETF OR ANY OTHER PERSON OR ENTITY FROM THE USE OF THE BLOOMBERG INDICES OR ANY DATA RELATED THERETO. BLOOMBERG DOES NOT MAKE ANY EXPRESS OR IMPLIED WARRANTIES AND EXPRESSLY DISCLAIMS ALL WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR USE WITH RESPECT TO THE BLOOMBERG INDICES OR ANY DATA RELATED THERETO. WITHOUT LIMITING ANY OF THE FOREGOING, TO THE MAXIMUM EXTENT ALLOWED BY LAW, BLOOMBERG, ITS LICENSORS, AND ITS AND THEIR RESPECTIVE EMPLOYEES, CONTRACTORS, AGENTS, SUPPLIERS, AND VENDORS SHALL HAVE NO LIABILITY OR RESPONSIBILITY WHATSOEVER FOR ANY INJURY OR DAMAGES—WHETHER DIRECT, INDIRECT, CONSEQUENTIAL, INCIDENTAL, PUNITIVE OR OTHERWISE—ARISING IN CONNECTION WITH THE EXTENDED DURATION TREASURY ETF OR BLOOMBERG INDICES OR ANY DATA OR VALUES RELATING THERETO—WHETHER ARISING FROM THEIR NEGLIGENCE OR OTHERWISE, EVEN IF NOTIFIED OF THE POSSIBILITY THEREOF.
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Glossary of Investment Terms
Authorized Participant. Institutional investors that are permitted to purchase Creation Units directly from, and redeem Creation Units directly with, the issuing fund. To be an Authorized Participant, an entity must be a participant in the Depository Trust Company and must enter into an agreement with the fund’s Distributor.
Bid-Ask Spread. The difference between the highest price a buyer is willing to pay to purchase ETF Shares (bid) and the lowest price a seller is willing to accept for ETF Shares (ask) when buying or selling shares in the secondary market.
Bloomberg U.S. Aggregate Bond Index. An index that is the broadest representation of the taxable U.S. bond market, including most U.S. Treasury, agency, corporate, mortgage-backed, asset-backed, and international dollar-denominated issues, all with investment-grade ratings (rated Baa3 or above by Moody’s) and maturities of 1 year or more.
Bond. A debt security (IOU) issued by a corporation, a government, or a government agency in exchange for the money the bondholder lends it. In most instances, the issuer agrees to pay back the loan by a specific date and generally to make regular interest payments until that date.
Capital Gains Distributions. Payments to fund shareholders of gains realized on securities that a fund has sold at a profit, minus any realized losses.
Coupon Rate. The interest rate paid by the issuer of a debt security until its maturity. It is expressed as an annual percentage of the face value of the security.
Creation Unit. A large block of a specified number of ETF Shares. Certain broker-dealers known as “Authorized Participants” may purchase and redeem ETF Shares from the issuing fund in Creation Unit size blocks.
Dividend Distributions. Payments to fund shareholders of income from interest or dividends generated by a fund's investments.
Duration. A measure of the sensitivity of bond—and bond fund—prices to interest rate movements. For example, if a bond has a duration of two years, its price would fall by approximately 2% when interest rates rise by 1%. On the other hand, the bond’s price would rise by approximately 2% when interest rates fall by 1%.
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Ex-Dividend Date. The date when a distribution of dividends and/or capital gains is deducted from the share price of a mutual fund, ETF, or stock. On the ex-dividend date, the share price drops by the amount of the distribution per share (plus or minus any market activity).
Expense Ratio. A fund's total annual operating expenses expressed as a percentage of the fund's average net assets. The expense ratio includes management and administrative expenses, but it does not include the transaction costs of buying and selling portfolio securities.
Face Value. The amount to be paid at a bond’s maturity; also known as the par value or principal.
Fixed Income Security. An investment, such as a bond, representing a debt that must be repaid by a specified date, and on which the borrower may pay a fixed, variable, or floating rate of interest.
Inception Date. The date on which the assets of a fund (or one of its share classes) are first invested in accordance with the fund's investment objective. For funds with a subscription period, the inception date is the day after that period ends. Investment performance is generally measured from the inception date.
Indexing. A low-cost investment strategy in which a fund attempts to track—rather than outperform—a specified market benchmark, or “index.”
Joint Committed Credit Facility. The Fund participates, along with other funds managed by Vanguard, in a committed credit facility provided by a syndicate of lenders pursuant to a credit agreement that may be renewed annually; each Vanguard fund is individually liable for its borrowings, if any, under the credit facility. The amount and terms of the committed credit facility are subject to approval by the Fund's board of trustees and renegotiation with the lender syndicate on an annual basis.
Mutual Fund. An investment company that pools the money of many people and invests it in a variety of securities in an effort to achieve a specific objective over time.
New York Stock Exchange (NYSE). A stock exchange based in New York City that is open for regular trading on business days, Monday through Friday, from 9:30 a.m. to 4 p.m., Eastern time.
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Principal. The face value of a debt instrument or the amount of money put into an investment.
Return of Capital. A return of capital occurs when a fund's distributions exceed its earnings in a fiscal year. A return of capital is a return of all or part of your original investment or amounts paid in excess of your original investment in a fund. In general, a return of capital reduces your cost basis in a fund's shares and is not taxable to you until your cost basis has been reduced to zero.
Securities. Stocks, bonds, money market instruments, and other investments.
Total Return. A percentage change, over a specified time period, in a fund's net asset value, assuming the reinvestment of all distributions of dividends and capital gains.
Treasury STRIPS. Fixed income securities that are sold at a significant discount to face value and offer no interest payments because they mature at par. STRIPS is an acronym for “separate trading of registered interest and principal securities.“
Volatility. The fluctuations in value of a mutual fund or other security. The greater a fund's volatility, the wider the fluctuations in its returns.
Yield. Income (interest or dividends) earned by an investment, expressed as a percentage of the investment’s price.
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Connect with Vanguard® ˃ vanguard.com
For More Information
If you would like more information about Vanguard Extended Duration Treasury ETF, the following documents are available free upon request:
Annual/Semiannual Reports to Shareholders
Additional information about the Fund's investments is available in the Fund's annual and semiannual reports to shareholders. In the annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the Fund's performance during its last fiscal year.
Statement of Additional Information (SAI)
The SAI provides more detailed information about the Fund's ETF Shares and is incorporated by reference into (and thus legally a part of) this prospectus.
To receive a free copy of the latest annual or semiannual report or the SAI, or to request additional information about Vanguard ETF Shares, please visit vanguard.com or contact us as follows:
Telephone: 866-499-8473; Text telephone for people with hearing impairment: 800-749-7273
Information Provided by the Securities and Exchange Commission (SEC)
Reports and other information about the Fund are available in the EDGAR database on the SEC’s website at sec.gov, or you can receive copies of this information, for a fee, by electronic request at the following email address: [email protected].
Fund's Investment Company Act file number: 811-01027
© 2021 The Vanguard Group, Inc. All rights reserved.
U.S. Patent No6,879,964
Vanguard Marketing Corporation, Distributor.
P 930 122021