My guesstimate for 2015 is about +200<p>You could also be inspired by the "jerk-off calculations" from Silicon Valley and take Toms numbers from 2010 at that point, referencing the amount of repos (at that time), the number of GH users (at that time) and the size of the repos (at that time) and then quantify these numbers into a model.<p>You can then use that model to estimate the 2015 numbers (holding constants like "they still use Ruby mostly" or "they haven't swapped out slow Ruby parts with high-performance X-language", etc.)<p>Based on their size though, adding that a lot of other code-hosting tools have since gone into shut-down mode, I'd say that even with major performance boosts, they must be (at minimum) around +100