New update out today adds stat tracking so you can know how much of the game you've experienced!
Did you know that in a typical playthrough you might see less than half of Press X to Not Die? Now you can know with the new progress stat that tracks how much of the game you've seen. It'll show up on the end game screen, in your achievements, and on the new Stats screen under "Stats & Leaderboards".
Along the same lines, there's also a new stat and achievement for how many of the different deaths you've experienced. You haven't lived until you've died 23 different ways!
http://store.steampowered.com/app/402330/