A couple of sites that document “browser usage” statistics:
Wondering if you have any sites that you prefer to use for these
This type of data can easily be skewed based on the “types” of
visitors for included sites. I don’t typically have this level of
logging turned on for my sites. However when the question gets asked
or I am interested, I tend to trust a “snapshot” of logging a
particular site to better understand the browsers that visit a site.