Windows has taken a significant drop over the years, going from being used by over 90% of people to being dropped down to under 60%
(programming.dev)
That looks like a methedology change at the very end.
Theres no way it dropped steadily for a decade then plummeted 20% in a month?
Its also interesting that iOS popped up from zero. What is that? If they're asking "what is your primary computer," Android and iOS would both be there and considerably higher, so what does iOS even represent here?