Vanguard Total Bond Market ETF (the Fund) seeks to track the performance of a market-weighted bond index. The Fund employs a passive management or indexing investment approach designed to track the performance of the Barclays Capital U.S. Aggregate Bond Index (the Index). The Index measures a spectrum of public, investment-grade, taxable, fixed-income securities in the United States, including government, corporate and international dollar-denominated bonds, as well as mortgage-backed and asset-backed securities, all with maturities of more than one year. The Fund invests by sampling the Index, meaning that it holds a range of securities that, in the aggregate, approximate the full index in terms of key risk factors and other characteristics. All of the Fund�s investments will be selected through the sampling process, and at least 80% of its assets will be invested in bonds held in the Index. The Fund�s investment advisor is The Vanguard Group, Inc.