Worldwide, shipments topped 113.5 million units, Dataquest said.
In the US alone, the market grew 21.6 per cent in 1999 over the previous year, with 43.8 million units shipped.
"There had been concerns that Y2K shutdowns in large business, government and education segments would slow growth in the market in the second half of 1999, but the numbers indicate it had only limited impact on overall growth in the PC industry," said Charles Smulders, an analyst for Dataquest in San Jose.
Dataquest's findings for the market growth in 1999 are very similar to predictions made by International Data Corp (IDC) late last year. Worldwide, IDC found that 1998 PC shipments increased about 12 per cent over 1997 and that 1997 global shipments were about 15 per cent above the previous year.
Compaq Computer remained the top vendor worldwide, while Dell Computer surpassed others in the US for 1999.
Globally, Compaq had 13.2 per cent share of the market, with more than 15 million units, while Dell had 9.8 per cent share with more than 11 million units.
Dataquest includes in the PC category desktops, deskside units, notebooks, ultraportables, laptops and transportables, but not PCs marketed with servers.
Smulders predicted growth in 2000 will slow by 4 per cent from 1999 levels. Much will depend on the industry's ability to persuade their customers to replace PCs more frequently. Businesses will be interested in getting smaller, less complex and cheaper products, he said.
The global market share and unit sales of the other top PC vendors were: IBM 7.9 per cent share, with 8.9 million units; Hewlett-Packard, 6.4 per cent share and 7.2 million units; Packard Bell NEC, 5.2 per cent share and 5.9 million units; Gateway, 4.1 per cent share and 4.6 million units; Apple, 3.4 per cent share and 3.8 million units. All others totalled 50 per cent of the shipments with 56.7 million units.
In the US, Dell led with 16 per cent share and 7 million units followed by Compaq at 15.7 per cent share and 6.8 million; Gateway at 9.1 per cent share and 3.9 million; HP at 8.7 per cent and 3.8 million; IBM at 7.2 per cent and 3.1 million; Apple at 4.4 and 1.9 million and all others combined at 38.9 per cent and 17 million units.
Dataquest said that the worldwide growth figures for 1999 were high but didn't surpass the 27 per cent increase in 1995 over the previous year. Growth in 1996 was nearly 18 per cent. In 1997 the increase was 15.2 per cent and in 1998 was 15.8 per cent.