IDC's latest Worldwide Quarterly Personal Computing Device Tracker offers new insight as to why the firm believes the PC market is set for a growth period a few years from now. From a report: Detachable tablets such as Microsoft's Surface line and Apple's iPad Pro will lead the growth as consumers have turned away from laptops in favor of these more versatile computing devices. Last year, 21.5 million of these devices were shipped and the number of units sold could reach as high as 45.9 million in 2021. Notebook computers and mobile workstations are another category that will see continued growth with shipments rising from 156.8 million units in 2016 to 163.7 million by the year 2021. Desktop computers are still decreasing in popularity and that trend is likely to continue with their sales predicted to decrease by 15 million a year leading up to 2021.