By MARTIN CRUTSINGER
AP Economics Writer

WASHINGTON (AP) — U.S. businesses increased their demand for industrial machinery, computers and autos in March, lifting factory orders for the fifth consecutive month.

Orders rose 3 percent after a 0.7 percent increase in February, the Commerce Department reported Tuesday. A key category that signals business investment plans jumped 4.1 percent after a small increase in February and a big decline in January. Excluding the volatile transportation sector, orders rose 2.6 percent.

The March increase pushed total orders to $462.9 billion, up 31.2 percent from the recession low it hit in March 2009.

Manufacturing has been one of the strongest sectors of the economy since the recession ended nearly two years ago. On Monday, the Institute for Supply Management reported that manufacturing activity rose for a 21st straight month in April.

A weak dollar is making U.S. exports cheaper overseas and tax cuts are encouraging business investment in capital goods.

For March, orders for durable goods - items expected to last at least three years - rose 2.9 percent. That's slightly better than a preliminary estimate the government reported last week.

Demand for nondurable goods rose 3.1 percent. Petroleum products increased 7.8 percent. Much of that gain reflected higher prices.

Orders for transportation rose 6.2 percent. Demand for autos increased 4 percent, nearly double the 2.2 percent rise in February. Automakers are benefiting from rising sales over the past several months.

Orders for commercial aircraft rose 0.9 percent after much bigger increases in the previous two months.