Stack Overflow Developer Survey Results 2016 on self-taught developers
Stack overflow 2016 survey.
40,183 responses from non-student developers reported that 69.1% of software developers appear to be self-taught, being the top education profile. This fact is misleading if one does not read the small print, which states that out of this 69.1%, only 13% report themselves as self taught only. That means that the remaining 56.1% did self-directed learning at some extend complementing their formal education, not by replacing it. 13% is nowhere near 69%, although the reading is positive: almost 1 in every 9 developers are excursively self-taught.
Almost the same percentage of developers who self-taught at some extend reported that they learn because they love it, being just second to getting job-related help. So 61.9% report they use Stack Overflow for their own fun and is not necessarily attached to their jobs, in the sense that they could learn different programming languages or technologies as a hobby.