Acetone in the dry erase is doing the heavy lifting in this scenario.

It’s a difference of about 300k tons/yr, but as others have mentioned, the price paid to Russia for these exports have plummeted. So in addition to exporting less, they are also getting paid substantially less as well.

I would expect that at 70% or maybe even 90%, but 99% isopropyl should absolutely not leave a residue behind.

How long ago did you get iso in there? If it was really recent, there’s a chance it may evaporate and be good as new. If it’s been a while, take solace in knowing it probably won’t get worse, at least.