To safeguard users from unnecessary liquidation triggered by abnormal market price, Mark Price is introduced to calculate the UPL.
The Mark Price is the price at which the contract is marked for unrealized PNL and liquidation purposes.
As for perpetual contract, the Mark Price is equal to the Index Price plus the Moving Average of Basis.
Please note that the mark price will not influence the realized PNL.
Funding Basis Rate = Funding Rate *( time of the next funding payment/ time interval of funding payment)
Mark Price = Index Price * (1+Funding Basis Rate)