Coinbase has 30M+ users. Extrapolating from that I'd say roughly 100M people use Bitcoin to some extent, and it's growing pretty rapidly (20% growth on /r/bitco

Coinbase has 30M+ users. Extrapolating from that I'd say roughly 100M people use Bitcoin to some extent, and it's growing pretty rapidly (20% growth on /r/bitcoin subscribers this year). Using means storing or transferring value in Bitcoin.