The two biggest U.S. oil companies increased production in the third quarter and reported lower but still robust profits.

© J. Emilio Flores for The New York Times

Not all states have gotten hit equally hard. The reasons are complex.

The S&P 500 slumped more than 2 percent for the first time in six months, rattling investors after a long stretch of gains.

The oil giant said Tuesday that it was acquiring assets from a Chicago company as it looks to start producing graphite, a key battery ingredient, by the end of the decade.