Inflation rose 2.9% on an annual basis in December, with the latest Consumer Price Index illustrating the Federal Reserve's challenge in battling stickier-than-expected price increases.

a price discrimination law passed during Franklin Delano Roosevelt’s presidency that was last enforced in the 1980s. Under the law, suppliers can discount large orders, but they must extend the ...

The change was slightly above analysts' expectations and is likely to bolster reluctance at the Fed to cut interest rates any further.