People can't go to work and log in, ergo, a noticeable drop in Windows 10 usage, because Windows is used by <i>a lot of people at work.</i><p>But, since we are looking at <i>relative</i> market shares, that means every other OS' share goes up, even if the actual number of users remains almost the same. (And the article points this out at the end.)<p>This will be followed by each of those OSs seeing massive drops in relative market share once people go back to work and all the dormant Windows 10 computers start running again.