The PC market (desktops, notebooks, and tablets) is expected to see almost half a billion units ship this year, 493.1 million to be exact, representing 7 percent year-on-year growth. Unsurprisingly, the key driver behind this growth will be tablets, accounting for 37 percent of the overall market and seeing 59 percent growth to 182.5 million units.

The latest estimates come from Canalys, an independent analyst firm which says it stakes its reputation “on the quality of our data, our innovative use of technology, and our high level of customer service.” Nevertheless, it’s worth emphasizing that these are estimates, though they do line up with what the broader industry is seeing: desktops are down, laptops are down, but tablets are up.

Canalys is basing these figures on worldwide demand for PCs in Q1 2013. Last quarter, the desktop market fell 10.3 percent, the laptop market declined 13.1 percent, but the size of the tablet market more than doubled with a 106.1 percent increase in shipments to 41.9 million units. Because shipments show no sign of slowing, Canalys forecasts global tablet shipments surpassing those of laptops in the final quarter of the year.

Here are the firm’s estimates for this year and the next four:

canalys table Canalys: Almost half a billion PCs to ship in 2013, as desktops and laptops dip but tablets grow 59% to 182.5m

In 2017, Canalys expects 713.8 million PCs will ship worldwide, with 64 percent being tablets, 25 percent laptops, and 11 percent desktops. Again, these are just educated guesses, so the numbers will undoubtedly change, but the overall trends are nonetheless interesting.

Windows 8 of course gets a mention, as it hasn’t been able to boost PC shipments much, though there is some hope with the free Windows 8.1 update. Microsoft has already detailed a lot about it, with more to come later this month.

“Microsoft will continue to innovate,” Canalys Senior Analyst Tim Coulling said in a statement. “New versions will come and its OS release cycle will gain speed. But it must address some of the criticisms that have been directed at the OS’s user interface or it risks losing even more ground to iOS and Android in the PC space.”

In fact, Canalys Research Analyst Pin-Chen Tang expects the new influx of Android devices to provide a boost enough for Google’s mobile operating system to take a 45 percent share of the tablet market this year, behind Apple at 49 percent (there are high hopes for the iPad mini). That leaves a mere 6 percent for Windows 8 and everything else.

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