XT.COM perpetual contract employs a unique mark price system to avoid unnecessary liquidations. Without this system, the mark price may deviate from the index price when the market is being manipulated, or illiquid, leading to unnecessary liquidations. All forced position deleveraging, settlement, forced liquidation, etc. use the mark price method.
Instead of the Last Price, the mark price is set as the mark price to avoid unnecessary liquidations.
Mechanism of mark price
For perpetual contract, the mark price equals to the underlying index price plus a decaying funding basis rate.
All the ADL contracts are adopting the mark price method. Please also be noticed that, this mechanism will only affect the forced liquidation price and unrealized P/L, and the realized P/L will not be affected.
Attention: That means you may see a positive or negative unrealized P/L immediately after your orders is executed. The reasons for the situation to occur is that there’s a slightly deviation between the mark price and the transaction price. This is a normal phenomenon, which does not mean the loss of money, but you must pay attention to your liquidation price to avoid the position being forced to liquidation prematurely.
Calculate the mark price of a perpetual contract
Marker Price = Median * (Price 1, Price 2, Contract Price)
Price 1 = Price Index * (1 + Margin *(Time to next Margin Call (in hours)/Margin Call Cycle))
Price 2 = Price Index + Moving Average (30-minute basis) * Moving Average (30-minute basis) * (1 + Margin Rate)
* Moving Average (30-minute basis) = Moving Average ((Bid1 + Ask1) / 2 - Price Index), sampled at 30-minute intervals.
* Median: Price1, Price2, Contract Price are the three numbers in the middle, e.g. if Price1 < Price2 < Contract Price, then the Marker Price is taken as Price2.
Please note that in case of large deviations between the spot price and the marker price (Abs(index price - marker price) / index price > 1%) due to possible market extremes or deviations of the price source, the marker price will be taken directly from price 2.
Additionally, when a stable and reliable source of reference data is unavailable, due to unusual distortions of the index price, etc., we will update the marker price with the latest traded price protection mechanism until it returns to normal. Latest Transaction Price Protection is a method of temporarily switching the contract price markers, using the latest transaction price of the contract itself plus a certain limit as the marker price so that the aggregation system has a way of calculating unrealized gains and losses and the leveling off line, etc., and at the same time, try to avoid unnecessary leveling off events at this time.