Sergei Galyonkin, developer of the Steam Spy analytics platform, has published a blog post that offers developers some intriguing (though disclaimer-ridden) insight into Valve's most recent Steam Summer Sale.
The most interesting piece of data, by far, is that roughly 24 percent of the games discounted during the Summer Sale (1050 out of 4390) accounted for at least $160 million in revenue during the promotion.
Galyonkin reports the other 3,340 games discounted during the sale (roughly 76 percent) generated less than $9 million in revenue, suggesting that the vast majority of the Steam Summer Sale's revenue boost was hoovered up by less than a quarter of the participating games.
"76 percent of games discounted during Steam Summer Sale sold less than 5,000 copies," wrote Galyonkin. "Probably significantly less than that...together those 76 percent of games made less than $9 million in revenue."
While there are clear risks in trusting Galyonkin's data (and, by extension, relying soley on it to make decisions about your game), Gamasutra's also been told off-the-record by more than one developer in the past that data culled from Steam Spy often matches up with their own accounting.
For more details on how Galyonkin pulled together data on the Steam Summer Sale, including revenue, copies sold, and how player behavior shifted during the promotion, check out his full blog post.