You can find some stats here: https://blog.malwarebytes.com/cybercrime/2016/06/ransomware-dominates-the-threat-landscape/
I think my wording then misled in a unintended way. When I said pay all or some of the ransom. You may find out that after paying they may tell you it's not enough and demand more. So in a sense you have paid some of the ransom, when the real amount they wanted wasn't revealed until you paid the first portion. The attacker has to weigh carefully here. If he keeps doing this and word gets out. People will stop even trying to pay and fight. Now income is lost. But if he does what he says, he's likely to get a higher return rather than a fight from his targets.
I really don't encourage the pay of the ransom but it's also not my data that is at risk. Paying them encourages them to continue after you but that is why you must understand the how it got in and how to fix your security hole. You can afford not to pay if you have good backup and can restore the backup after you fix your security vulnerability. But not so much if you don't have a good backup of your data and it's your only extant data and you need the data back. Payment is not a great option but it maybe your only option. I would notify law enforcement of the computer crime though.