US stocks gained after cooler-than-expected producer price index data soothed inflation concerns. The numbers on Tuesday showed wholesale inflation rose 0.2% in December on a monthly basis, compared to an estimated 0.4% increase. The reading climbed 3.3% from a year ago, below the projected 3.5% gain.

Stock-market investors are turning jittery over something which has apparently happened only two times in the bond market since the early 1980s: The 10-year Treasury yield has jumped by about as much as the Federal Reserve has cut interest rates over the same period of time.