NEW YORK (AP) — Strong demand for machinery drove up Caterpillar's profit 44 percent in the third quarter and the company expects even stronger sales next year.

Caterpillar's stock rose almost 5 percent in premarket trading, increasing $4.26 a share to $91.65.

The world's largest maker of construction and mining equipment earned $1.14 billion, or $1.71 per share, in the third quarter, compared with $792 million, or $1.22 per share, a year earlier. Revenue surged 41 percent to $15.72 billion.

Excluding its $7.6 billion acquisition of surface mining equipment maker Bucyrus International Inc., Caterpillar earned $1.93 per share on revenue of $14.58 billion.

Analysts polled by FactSet Research were expecting a profit of $1.63 per share on $14.84 billion in sales.

Caterpillar predicts higher 2011 earnings than it forecast earlier. It expects to earn $6.75 per share on sales of $58 billion. It previously forecast profit of between $6.25 and $6.75 per share on revenue of $56 billion to $58 billion.

Excluding the impact of Bucyrus, Caterpillar expects to earn about $7.25 per share on revenue of $56 billion. Analysts project a profit of $6.76 per share on sales of $56.59 billion.

It projects revenue next year will increase 10 and 20 percent over 2011 to between $63.8 billion and $69.6 billion.

The Peoria, Ill. company is continuing to add jobs — nearly 5,000 between June and September alone. As of Sept. 30, it had about 149,000 employees, up more than 20 percent from a year earlier, including staff gained from acquisitions. About 5,600 of those jobs were added in the United States.