IDC numbercrunchers claim CPU shipments have declined at the steepest rate since 1996, and they expect the downward spiral will continue through the first half of 2009.

Sequentially, the number of units shipped went down by 17 percent, while revenue dropped 18 percent for a total of $6.78 billion in Q4. In spite of the dismal last quarter, the marked in 2008 still grew by 10 percent in number of units and 0.9 percent in revenue.

The IDC points out that without Intel's Atom, things would have been much worse, and claims unit shipments would have dropped by 21.7 percent in Q4. Intel should probably thank the Atom for a 1.1 percent increase in market share, for a total of 81.9 percent in Q4. AMD lost some share, ending at 17.7 percent, while VIA took 0.4 percent.

In 2008 as a whole, AMD market share dropped by 3.1 percent, while Intel's went up by 2.9 percent.

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