WASHINGTON — Prices for U.S. Treasury debt plunged for the fifth straight trading session Wednesday, and the yield on the benchmark 10-year note spiked to its highest level since October.

Money poured out of bonds and into stocks after rosy words on Tuesday from the Federal Reserve gave traders confidence that the economic recovery is strengthening. Major stock market averages are at or near four-year highs.

Treasury yields – and interest rates that take their cues from Treasury yields, including mortgage rates – remain near all-time lows. So while mortgage rates may creep up, they should remain historically low.

Even with the economy getting stronger, the Fed plans to keep short-term interest rates near zero through 2014. And demand is strong for long-term Treasury notes because the dollar and the U.S. government still look like safer bets than foreign venues.

More evidence of the hunger for U.S. debt came Wednesday, when the Treasury Department auctioned $13 billion in 30-year bonds. Bids came in higher than current market prices.