Futures markets are also expecting a rate cut. Investors peg the chances of a quarter-point interest rate cut at nearly 96%, according to the CME FedWatch Tool, a measure of market sentiment.

A Federal Reserve interest rate cut in September, the first this year, followed perhaps by another before year-end remains the base forecast for most economists polled by Reuters amid rising concerns about the health of the world's biggest economy.

Yields on the debt are the biggest determinant of how much it costs to buy a home, fund a business, or pay the interest on the national debt.