Ahead of Apple's announcements of its own numbers for the June quarter, Gartner and IDC have released competing reports with very different results for Apple's unit sales and market share for the time period.

Gartner's numbers show Apple with 1.42 million Macs shipped in the U.S. during the quarter, representing 2.5% year-over-year growth and a market share gain of .2%, while IDC reported that Apple sold but 1.21 million Macs, a 12.4% year-over-year decline and a market share drop of .9%.

IDC shows Apple slipping to the #5 spot in the U.S., down from #4 in the first quarter. Gartner's report maintains Apple as the #4 vendor. Apple's total sales are not high enough to place the company in the top five for the global market.

In a research note obtained by The Mac Observer, Barclay's Capital analyst cautioned his clients not to take either report too seriously when it comes to Apple, saying, "Note that we do not believe that the IDC or Gartner data for Apple is accurate given that Apple generally does not provide any guidance to industry data sources prior to their own earnings report."

Apple will make its announcement next Tuesday, July 21st, 2009.

For their part, both firms refer to the numbers as "preliminary," with adjustments likely in coming weeks.

Global & Trends

Both reports said that overall PC unit sales declined year-over-year, but that the decline was less than anticipated. IDC said unit sales were down 3.1% globally, much better than the 6.3% decline the firm had anticipated. Gartner said overall unit sales declined 5%, again ahead of the 9.8% decline it had expected.

"These results are a very positive indicator for the second half of the year," Loren Loverde, program director for IDC's Tracker Program, said in a statement. "We are seeing continued demand from consumers and limited impact from supply chain factors such as inventory balancing. New product launches in the second half of the year combined with seasonal growth and greater economic confidence resulting from factors such as government stimulus, a more liquid housing market, relatively stable stock market and interest rates, and progress in the auto and financial industries, should support the expected return to growth by year-end."

Portables are the big growth area, particularly among consumers, with strong netbook sales helping to propel Acer's unit sales up 23.7% year-over-year, representing a market share gain of 2.7 percentage points to 12.7%, according to IDC. Gartner reported 34.2% sales growth and a 4 point gain to 13.5% of the global PC business.

One area both research firms agreed on was the drubbing Dell took with an 18.7% year-over-year decline reported by Gartner for the U.S. and and an 18.9% decline reported by IDC. Still, Dell's unit sales were enough to keep the company as the #2 PC vendor in the world, just behind HP.