For November, Yosemite accounted for 36.6 percent of all instances of OS X tallied by Net Applications, which estimates operating system user share by counting visits to the websites operated by its clients.
By comparison, OS X Mavericks, Apple’s 2013 upgrade, ended November of that year – also its first full post-launch month – with a Mac-only user share of 32 percent.
Yosemite’s pace was the fastest ever for an edition of OS X, beating not only Mavericks but also posting a user share 85 percent larger than 2012′s Mountain Lion and 114 percent greater than 2011′s Lion at their one-month marks.
Yosemite’s quicker tempo was in marked contrast to the slower pace of Apple’s iOS 8, which continues to lag behind that of last year’s iOS 7. Yosemite’s adoption also showed that the vocal complaints of still-crippled Wi-Fi have not kept Mac owners from upgrading.
As in October, last month’s gains by Yosemite came mostly at the expense of Mavericks, although Mountain Lion and Lion also lost larger-than-average amounts of user share. Mavericks’ drop of 13.5 percentage points – the OS ended November with 38.4 percent – was the largest since its launch.
The quicker climb of Yosemite was due to its head start: Unlike Mavericks, Yosemite was offered to Mac owners as a beta, and appeared about a week earlier in its release month.
According to Net Applications, 18 percent of all Macs ran an unsupported edition of OS X in November. Apple has dropped security support for Lion and earlier versions, meaning that it no longer provides patches for vulnerabilities.
The free Yosemite upgrade can be obtained from Apple’s Mac App Store, and supports iMacs as old as mid-2007, MacBook Pro notebooks from late 2007 on, and MacBook Air laptops from late 2008 going forward.