VANGUARD SCOTTSDALE FUNDS VANGUARD MTG BACKED SECS ETF

The Vanguard Mortgage-Backed Securities ETF employs an indexing investment approach designed to track the performance of the Bloomberg Barclays U.S. MBS Float Adjusted Index. This Index covers U.S. agency mortgage-backed pass-through securities issued by the Government National Mortgage Association (GNMA), the Federal National Mortgage Association (FNMA), and the Federal Home Loan Mortgage Corporation (FHLMC). To be included in the Index, pool aggregates must have at least $250 million currently outstanding and a weighted average maturity of at least 1 year.