Worldwide personal computer (PC) shipments in 2004 rose 14.7% year-on-year to touch 177.5 million units, but in 2005 the growth is expected to slow down to 10%, according to analyst firm IDC.Total shipments in 2004 were more than 26% over 2000 volumes, and IDC expects growth of roughly 10% in 2005 before shipment growth slows to single digit.In the fourth quarter of calender 2004, worldwide PC market remained strong with a growth of 13.7%, driven by the small and medium business segments and holiday consumer demand, according to IDC's worldwide quarterly PC tracker.Total shipments rose to 51.5 million units for the quarter, marking the seventh consecutive quarter of double-digit growth in worldwide PC shipments."Business demand and growth in key regions continue to drive the market," said Loren Loverde, director of IDC's worldwide quarterly PC tracker."Although we saw a seasonal rise in consumer shipments, business remains a larger market and has been growing faster since mid-2004. Ongoing PC replacements and new investment should continue to drive commercial growth at least through the end of 2005," Loren Loverde said.Following another quarter of strong growth, Dell is now the uncontested market leader. After ceding the top spot to HP in the fourth quarter of 2002 and 2003 following HP's merger with Compaq, Dell managed to distance itself from HP by a full point of marketshare in the fourth quarter, and seems to have the momentum on its side.Gateway and Apple made significant improvements. While still losing share, Gateway showed the first signs of meaningful improvement following its merger with Emachines.Similarly, Apple saw a significant kick from its new Imac and attention related to its music business, reinvigorating a business that had been struggling to keep pace with the market.In the US, though the consumer market appeared to be somewhat weak for the fourth quarter due to a difficult year-on-year comparison, overall growth remained fairly steady, hovering in high single digits, IDC said.In Europe, PC growth continued to benefit from a strong Euro, portable adoption and commercial investment. EU expansion and aggressive pricing are also helping fuel growth.The commercial market continues to sustain growth in Japan despite limited consumer growth, while in the rest of asia-pacific, regional growth was in-line with expectations despite continued soft demand in Korea, IDC said.