ByJohn S. McClenahen Both personal income and spending in the U.S. rose in January, although income rose at only about half the expected rate. Personal income increased two-tenths of a percentage point -- $18.4 billion -- between December 2003 and January 2004, the U.S. Commerce Department reported on March 1. Economists generally had been looking for a 0.4% increase. Personal consumption expenditures increased 0.4% ($32.1 billion), a tenth of a percentage point better than expected. "We expect some improvement [in consumption] over the balance of the [first] quarter as auto sales rebound and after-tax income benefits from big personal tax rebates," says UBS Investment Research, New York.