You need a good understanding of computers to become a decent programmer. If you feel you have that and you're interested in the topic, age won't matter. I also didn't take a proper class until 24, but did lots of IT stuff before that. Learning to program was like unlocking a castle of mystery for me. So go ahead!
Pudong was never a ghost city either. A more complete sample would be desirable. How about South China Mall? That was one of the prime examples, wasn't it?
None of this is new or surprising. It would be more interesting to apply this kind of visualization to industries, % or part-time jobs, freelance workers, etc.