AGG is essentially the same type of broad U.S. bond ETF as BND, with a nearly identical dividend yield (4.05%) and one-year return (-3.1%). Both show the same pattern of bond prices being pressured during a rate-hiking cycle.

Since both funds hold the entire U.S. investment-grade bond universe, performance differences are negligible — the choice usually comes down to broker access or account structure. If you already hold BND, there's little practical benefit to adding AGG as well.