Total bond market index fund.
In plain English
A total bond market index fund owns a wide cross-section of investment-grade U.S. bonds, Treasuries, corporate bonds, and mortgage-backed securities, across many maturities, weighted to mirror the broad bond market. It is the fixed-income counterpart to a total stock market fund: one cheap, diversified holding for the bond side of a portfolio. Its price rises and falls with interest rates, and its yield reflects the mix of bonds it holds. It will not shoot up like stocks, and it can lose value when rates rise, but it adds ballast and income that offset stock volatility.
01Why it matters
A single total bond fund is the simplest way to own diversified fixed income, so understanding it helps you build the stabilizing side of a portfolio without picking individual bonds.
02The math, step by step
You hold a total bond market index fund alongside a stock fund. When stocks drop, the bond fund's steadier value and interest cushion the fall, smoothing the ride even though it grows more slowly.
03What this is NOT
A total bond fund is NOT risk-free. Its price falls when interest rates rise, so it can post losses, though it is far steadier than stocks and adds diversification.
04Receipts
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