Steam is currently seeing a big decline in the number of people playing games (and even having Steam open on their computers) since January of this year.
As Steam Spy creator Sergey Galyonkin points out, it's not unusual to see a drop in players during the warmer season, but this year’s summer decline sees numbers going down by 17 percent, compared with 9 percent last year.
Data from the past three years logged by SteamDB shows that Steam typically sees user counts peak annually in January, decline or stagnate in the summer, and then increase toward the beginning of the new year.
If there's a much larger decline this summer, it could imply Steam’s usual rate of growth is slowing down, or that the platform simply hit its massive user peak earlier in the year from huge sales of PlayerUnknown's Battlegrounds.
The battle royale title is still the most popular game on Steam, but its numbers have decreased significantly since earlier this year. Galyonkin notes that the latter seems unlikely, as this decrease by itself isn't enough to explain Steam’s current decline.
It's likely that Steam's numbers will increase as the end of the year grows closer, but as for now, there’s no clear indication of what's causing user numbers to dwindle.