21mio, some pages backwards. coinmarketcap doesn't read forums.
- total supply will be just slightly below 21 mio coins
- available supply atm is around 1.6 mio (dcr devs + airdrop) + around 8.9k coins/day * 7 days since launch = aprox. 1.662 mio coins.
Problem is, Coinmarketcap needs the way how to get this from dcrd or any other place automatically, which seems not possible atm. Lets hope devs will fix this asap, because it can gain additional visibility for DCR.
*edit
At current prices (400usd/btc, 0.00282) the DCR capitalization is around 1.9 mio USD.