The Coinmarketcap approach is used to determine the Circulation supply
[1] According to this approach, the circulation supply is calculated using the following formula: Circulating supply = Emission limit - Liquidity reserve - Partners fund - Development fund - Swap reserves - Staked on masternodes - Masternode stabilization fund - Current accumulation fund
In accordance with this formula, an API endpoint has been developed that shows the value of the Circulation supply in real time:
[2]