No revenue estimate for GOG — its rating/review counts don't calibrate to sales the way Steam's do. The Steam version is estimated at $63.3M — a different platform, not this one.

Prison Architect

Build and manage a Maximum Security Prison. As the sun casts it’s early morning rays on a beautiful patch of countryside the clock starts ticking. You’ve got to crack on and build a holding cell to detain the job-lot of maximum security prisoners that are trundling to your future prison on their yellow bus. As your workmen lay the last brick you don’t have a moment to let them rest as they need to get started on the first proper cell block so you can make room for the next prisoner intake. Once they’ve all got a place to lay their weary heads the fun can really start. You’ll need a canteen, infirmary and a guard room, oh, and don’t forget to plumb in a toilet, or things will get messy, but what about a workout area? Or solitary confinement cells? Or an execution chamber? Inspired by Dungeon Keeper, Dwarf Fortress and Theme Hospital and with over 1 million players having spent time inside, Prison Architect is the world’s best lock-em-up. Play through the awesome 10 hour campaign Build your own supermax or liberal paradise in sandbox mode Try to escape from your or anyone else's prison in Escape mode