Yes Bitcoin is much more popular than Dollar, we can see the development of Bitcoin from the beginning of 2017 until now October 2017, how much growth percentage? my estimates are likely to be nearly ± 70%. Many predict that Bitcoin will replace Physical Currency (FIAT) I think for the short term it will be difficult, long term Bitcoin can replace Dollar or Physical Currency, the cause is Bitcoin Growth which is not affected by global economic conditions. Because Bitcoin is not controlled by a Central Bank in any country.