Hacker News Reader

I think this nails it. Given both python and R, these people will pick R because the motivation for using R is very clear, it does data analysis and statistics. Whereas python kinda does everything and that makes it a bit more tricky to understand.

Second after Excel?

Fair, although I would say Excel and R are serving two separate purposes. But yes, Excel is of course #1

> Fair, although I would say Excel and R are serving two separate purposes.

It's true that they target different use cases overall (obviously with some overlap), but Excel tends to be used for lots of things that would be better handled with a different tool, because it's what people know.

Matlab has a substantial userbase, too.

Agreed, but IMO R >> MatLab and SAS over the past ~10 years. Both Matlab (physics??) and SAS (pharma/financial) seem to have further sunk into deep niches.

Matlab is still big in engineering as well. Matlab+Simulink in particular seems to have a fairly entrenched niche.