Given how a LOT of the stuff today is behind paywalls and Archive.today breaks through most of them and Archive.org doesn't, your "99%" figure is way, way off when it comes to popular stuff.
Anyway, I donate to both the Archive.today and Archive.org. They're extremely valuable to me. I feel like Archive.today is in a dire situation when it comes to funding so I donate more than double to them each month.
If you're able, please donate to these sites. They are running on fumes. And take a look at my profile for a list of other orgs to donate to.