PC Shipment Numbers: A Tale Of Two SpinsPC Shipment Numbers: A Tale Of Two Spins

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Worldwide PC shipments are either up or down, depending on how you define the term "personal computer."

If you're the sort of person who's inclined to see the glass as half-empty, you may find recent reports from research firms International Data Corporation (IDC) and Gartner to your taste. They paint a bleak picture of the PC industry, a vision reinforced by Dell's decision to go private.

IDC in January said that worldwide PC shipments reached only 89.8 million units in the fourth quarter of 2012, down 6.4% from the same quarter in 2011. As if to underscore the dismal state of PC sales, the firm noted that the 6.4% figure was worse than the predicted 4.4% decline and that the launch of Windows 8 failed to buoy dwindling interest in PCs.

Gartner's numbers were no sunnier. It reported worldwide PC shipments of 90.3 million units for Q4 2012. Mikako Kitagawa, principal analyst at Gartner, noted in a statement that tablets have changed the device landscape by becoming, for many, an alternative to a PC rather than a complementary device.

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For those determined to see the glass as half-full, or even to chip away at the glass until the contents reach the rim, research firm Canalys has the report you're looking for.

According to Canalys, the PC industry is booming. Worldwide PC shipments rose 12% year-on-year in Q4 2012 to reach 134 million units.

But to arrive at that number, you have to include tablets -- Canalys refers to them as "pads," as if to taunt Apple's trademark lawyers -- in your tally. By Canalys' count, one in every six PCs shipped during the quarter was an iPad.

"Apple continued to lead the PC market, shipping 27 million units and taking its share over 20% for the first time," the firm said. That breaks down to 22.9 million iPads and 4.1 million Macs, as Apple reported.

If you ignore the fact that Apple shipped 22% fewer Mac computers than it did during the same period a year earlier, you can indeed assert that PC sales are rising. Nonetheless, there continue to be some meaningful distinctions between Mac OS X computers and iOS devices, to say nothing of the differences between PCs and tablets.

However, Canalys VP and principal analyst Chris Jones doesn't see the need to distinguish between tablets and PCs. "Does it make any sense to not include tablets as PCs?" he asked in an email. "Yes we have tablets/pads as one of the four categories (desktop, notebook, netbook, pad) of the 'Client PC market.' We made the decision to do this three years ago when the first iPad was launched. Our data clearly shows the impact of the pad cannibalization on the other products -- especially consumer PCs (which are less likely to be replaced now) and netbooks."

Loren Loverde, program VP at IDC, said in an email that including tablets in PC shipments is a matter of perspective and spin. "There are similarities between PCs and tablets, but their positioning, function, pricing and usage is still quite different," he said. "That's a core reason we continue to keep them separate."

Loverde said that today's devices can be grouped other ways, to assess the total number of devices accessing the Internet or the breadth of a common ecosystem. IDC, for example, combines PCs, tablets and smartphones in its "Smart Connected Devices" category.

But drawing lines to define devices isn't easy, which is why we see terms like "phablet" to describe Samsung's Galaxy Note line, which straddles the border between phone and tablet. This categorical fuzziness could be seen back in 2007 when Steve Jobs introduced the first iPhone. He described it as, "a widescreen iPod with touch controls, a revolutionary mobile phone, and a breakthrough Internet communications device."

Apple said it sold 12.7 million iPods in its fiscal first quarter (Q4 2012). But during this period, it sold 47.8 million iPhones, every one of which is also, more or less, an iPod touch. So how many iPods did Apple really sell? As far as Apple's iTunes Store is concerned, the relevant number for the quarter is 60.5 million.

Similarly, Microsoft's Surface line is neither fish nor fowl, so to speak. Loverde observed that Surface fits somewhere between the core PC and tablet markets. "We count them as tablets based on the slate design," he said, adding that IDC doesn't expect much demand for Surface in the short term due to widely recognized limitations.

As Loverde sees it, the traditional definition of PC is still useful because most people understand that the term refers to a distinct product type.

"There are changes to the number of devices people own, as well as in the way people use devices, value mobility, access the Internet, and other activities that could be called personal computing, but that would apply equally to browsing the Web on a phone and doesn't reflect the common understanding of what PC is," he said. "In this broad context, a literal reading of 'personal computer' is ambiguous -- but it doesn't help much to expand the coverage."