Valve explained Steam's Top 10 list last week. On May 13-19, you can look at the full list of top 10 best-selling games on Steam from below:
1-PLAYERUNKNOWN’S BATTLEGROUNDS
2-Conan Exiles
3-Grand Theft Auto V
4-Wizard of Legend
5-House Flipper
6-The Forest
7-Tom Clancy’s Rainbow Six Siege
8-Stardew Valley
9-Hellblade: Senua’s Sacrifice
10-Tom Clancy’s Rainbow Six Siege