[Encosia]

If you're looking at overall traffic, combining mobile, tablet, and desktop/laptop, that's probably in the ballpark of correct, but that simplistic measure isn't something I would allow to drive too many decisions.

If your site depends at all on user generated content (even comments), one active desktop/laptop user is probably worth hundreds or thousands of screenboard users. On my non-corporate-facing sites, IE is still 30+% of desktop usage, even though it's only 5-10% of overall usage.

Also, if you provide an untested experience to your IE users, you're probably bouncing many more users than you realize. Very few people return to a site that doesn't work in their default browser.

nb: I'm typing this in Chrome on a MBP.