Plummeting desktop shipments in the first quarter dragged down the PC industry to its lowest level in at least seven years, a market research firm said Friday.

PC shipments in the quarter fell 8.1% from the same period a year ago to 66.5 million units, iSuppli said. Compared with the previous quarter, shipments dropped by 14.4%.

The results were worse than iSuppli's earlier forecast of a 4% decline. "The worldwide recession sparked by the credit crisis slammed PC shipments for the second quarter in succession during the first three months of 2009,” iSuppli analyst Matthew Wilkins said in a statement.

Falling desktop shipments were a major factor in the market decline, iSuppli said. First-quarter shipments in the quarter fell 23% from a year ago. In contrast, laptop shipments grew by 10%.

There were no changes in the rankings of the world's top five PC manufacturers. Hewlett-Packard remained the leader with a 19.7% market share. Dell held on to the No. 2 slot with a 13.2% share, despite an 18.7% drop in shipments. Hewlett-Packard shipments were flat year to year.

"Dell's performance in the first quarter was heavily influenced by its weak desktop shipments, which dragged down its overall market share," Wilkins said.

Rounding out the top five vendors were three Asian PC makers, Acer, Lenovo, and Toshiba, which had market shares of 11.1%, 6.7%, and 5.2%, respectively.

Shipments of inexpensive mini-laptops, called netbooks, remained strong. The fastest-growing PC segment will account for 14% of global PC shipments this year, up from 9% last year, iSuppli predicts.

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