The numbers do seem a bit "pulled out a hat, like a rabit " but iIknow from experiance that lots of people end up with ransomware on their pc's and just pay up. Most times I get to them before they pay.
If they do pay via CC then a charge back is often sucssesful. On eof the biggest problems is people using XP logged in as a local admin, I always make sure people home main account is non admin. Then you know if they want to install a application they have to use the special admin account.
Mines the one with autoruns/process explorer/spybot in the pocket.