Americans increased their spending more slowly in March, suggesting some are worried that their paychecks aren't growing fast enough.

The Federal Reserve has boosted its outlook for U.S. economic growth this year and is slightly more optimistic about the unemployment rate, reflecting improvements in recent months.

The Federal Reserve sketched a mildly brighter view of the economy Tuesday after a burst of hiring since its last meeting in January. It took no further steps to aid the recovery and repeated its plan to keep short-term interest rates near zero through 2014.

U.S. companies will have to keep hiring steadily to meet their customers' rising demand. That's the message that emerged Wednesday from a report that employers are finding it harder to squeeze more output from their existing staff.

Growth in U.S. worker productivity slowed at the end of last year, while labor costs rose. Fewer gains in worker output suggests employers must add workers if they want to meet higher demand.

Federal Reserve Chairman Ben Bernanke reiterated his concern Thursday that chronic long-term unemployment threatens to reduce the nation's supply of skilled workers.

President Barack Obama on Monday sent Congress a new budget that seeks to achieve $4 trillion in deficit reduction over the next decade while at the same time showering billions of dollars of increased spending on areas aimed at giving the economy a quick boost.

Americans' income rose in December by the most in nine months, a hopeful sign for the economy after a year of weak wage gains. But consumers didn't spend any more than they had in November.