Although Valve generally keeps Steam's performance figures under wraps, FADE estimates that the service raked in just shy of $1 billion last year. Revenue supposedly reached $970 million in 2010 and unsurprisingly, December was the service's best month with $213 million in sales. FADE reports that over 180 games cracked the $1 million sales mark with the Call of Duty franchise being the top seller.
COD: Black Ops was the highest grossing title with $98.2m, while 2009's Modern Warfare 2 pulled in $39.4m. Valve's own Left 2 Dead 2 was the third bestselling game with $36m in revenue, while Bad Company 2 and Civilization V hit $25.4 and $21.9m, respectively. Portal, Fallout: New Vegas, Metro 2033, Mafia II, and Dawn of War II: Chaos Rising occupied the bottom five slots, selling $10 to $20m.