A. Security Valuation: Securities are valued as of the close of trading on the New York Stock Exchange (generally 4 p.m., Eastern time) on the valuation date. Equity securities are valued at the latest quoted sales prices or official closing prices taken from the primary market in which each security trades; such securities not traded on the valuation date are valued at the mean of the latest quoted bid and asked prices. Bonds and temporary cash investments are valued using the latest bid prices or using valuations based on a matrix system (which considers such factors as security prices, yields, maturities, and ratings), both as furnished by independent pricing services. Structured debt securities, including mortgages and asset-backed securities, are valued using the latest bid prices or using valuations based on a matrix system that considers such factors as issuer, tranche, nominal or option-adjusted spreads, weighted average coupon, weighted average maturity, credit enhancements, and collateral, as furnished by independent pricing services. Investments in Vanguard Market Liquidity Fund are valued at that fund's net asset value. Securities for which market quotations are not readily available, or whose values have been affected by events occurring before the fund’s pricing time but after the close of the securities’ primary markets, are valued by methods deemed by the valuation designee to represent fair value and subject to oversight by the board of trustees. These procedures include obtaining quotations from an independent pricing service, monitoring news to identify significant market- or security-specific events, and evaluating changes in the values of foreign market proxies (for example, ADRs, futures contracts, or exchange-traded funds), between the time the foreign markets close and the fund’s pricing time. When fair-value pricing is employed, the prices of securities used by a fund to calculate its net asset value may differ from quoted or published prices for the same securities.
B. Foreign Currency: Securities and other assets and liabilities denominated in foreign currencies are translated into U.S. dollars using exchange rates obtained from an independent third party as of the fund’s pricing time on the valuation date. Realized gains (losses) and unrealized appreciation (depreciation) on investment securities include the effects of changes in exchange rates since the securities were purchased, combined with the effects of changes in security prices. Fluctuations in the value of other assets and liabilities resulting from changes in exchange rates are recorded as unrealized foreign currency gains (losses) until the assets or liabilities are settled in cash, at which time they are recorded as realized foreign currency gains (losses).
C. To Be Announced (TBA) Transactions: A TBA transaction is an agreement to buy or sell mortgage-backed securities with agreed-upon characteristics (face amount, coupon, maturity) for settlement at a future date. The fund may be a seller of TBA transactions to reduce its exposure to the mortgage-backed securities market or in order to sell mortgage-backed securities it owns under delayed-delivery arrangements. When the fund is a buyer of TBA transactions, it maintains cash or short-term investments in an amount sufficient to meet the purchase price at the settlement date of the TBA transaction. The primary risk associated with TBA transactions is that a counterparty may default on its obligations. The fund mitigates its counterparty risk by, among other things, performing a credit analysis of counterparties, allocating transactions among numerous counterparties, and monitoring its exposure to each counterparty. The fund may also enter into a Master Securities Forward Transaction Agreement (MSFTA) with certain counterparties and require them to transfer collateral as security for their performance. In the absence of a default, the collateral pledged or received by the fund cannot be repledged, resold, or rehypothecated. Under an MSFTA, upon a counterparty default (including bankruptcy), the fund may terminate any TBA transactions with that counterparty, determine the net amount owed by either party in accordance with its MSFTA, and sell or retain any collateral held up to the net amount owed to the fund under the MSFTA.
D. Repurchase Agreements: The fund enters into repurchase agreements with institutional counterparties. Securities pledged as collateral to the fund under repurchase agreements are held by a custodian bank until the agreements mature, and in the absence of a default, such collateral cannot be repledged, resold, or rehypothecated. Each agreement requires that the market value of the collateral be sufficient to cover payments of interest and principal. The fund further mitigates its counterparty risk by entering into repurchase agreements only with a diverse group
