Profit and Loss Calculation of Inverse Perpetual Contract

Unrealized contract profit and loss
Long position: contract unrealized profit and loss = (1/opening average price-1/mark price) * contract size * contract face value
Short position: contract unrealized profit and loss = (1/mark price-1/average opening price) * contract size* contract face value

Liquidation profit and loss (excluding capital costs and transaction fees)
Long position: contract realized profit and loss = (1/opening average price-1/closing price) * contract size * contract face value
Short position: contract realized profit and loss = (1/closing price-1/average opening price) * contract size* contract face value

Realized profit and loss calculation (including funding costs and transaction fees)
Realized profit and loss = closing profit and loss-(all costs)
All costs = opening commission fee + closing commission fee + funding cost

Average opening price = contract face value * total contract size / contract value
Contract value = [(contract face value*contract size1 / price1) + (contract face value*contract size 2/price2) + (contract face value*contract size 3/price3)....]