yep, I am working on simple stats page for DCR - but more precise than approx. calculation = it will be connected directly to chain through dcrd web socket rpc and will expose simple call for actual amount of coins in existence (e.g. REQ: /dcr/v1/availableSupply ... RES: 1662000.00000000), so e.g. Coinmarketcap or others can use it.
Definitely get in touch with the devs about this too. This is quite an important feature that Decred needs in the near future.