But if you're B2B then, you're not selling to that 1%, you're selling to a range of companies.

So 1% of end users having IE9 translates to 10% of your customers having (some) users with IE9.

Sometimes you're not even selling to companies, you're selling to partners or resellers selling to companies, so now that 10% of companies translates to 60% of your partners / resellers having (some) companies which themselves have (some) users with IE9.

So what was 1% of users can translate to much more than 1% of revenue lost just by dropping support.

And that's before I get started on how general those analytics are rather than breaking it down to office workers during work. Again, if your business is selling SaaS that targets workers then you'll likely come across a client with a need for older IE support sooner rather than later.

There's another reason why B2C is fine to drop support:

People are resourceful, if you have a website which breaks in IE9 then they'll probably just switch to chrome and it'll work fine if it's something they really want.

Companies however tend to be less flexible, if they know they have IE9 installed they'll insist on having "IE9 support" in the acceptance criteria, even if it's only installed on a few machines which likely will never be used with your software.

I'm actually happy to see bootstrap, jquery etc drop IE9 support because it makes it much easier during negotiation to drop support and push back against such proposals.

IE9 is still in extended support until April due to the fact it's the most recent IE that can run on Vista, and Vista is still in extended support until April 11.