How does level system actually work?

Not that I'm complaining or something, I'm just curious.

My first giveaway was for Labyronia RPG (SGTools valued it for 0,30$). After it ended and the winner marked Received, I immediately jumped to Contributor Level 1. This surprised me in a positive way, but I didn't think too much of it.

Now, let's read the FAQ:
"Levels increase almost exponentially, meaning each level requires double the contributions of the previous level. For example, level 4 would require double the contributions of level 3, and level 3 would require double the contributions of level 2."

So, level 2 would require double the contributions of level 1?... I don't think so. Since that time I've given away some other games, valued 8$ by SGTools, and my level is 1.32. 8$ is 26 times more than 0,3$, so how does it actually work? My best guess is that Level 1 is very easy to get, and then it starts getting harder... But that FAQ is kinda misleading.