The graph below shows the hypothetical² price for a BitMEX Bitcoin UP contract XBT7D_U110 (right axis) as the .BXBT30M index changes (left axis).
We have provided prices for each day (12:00 UTC) throughout the seven-day life of the product.

Listing date and time is Friday, 1 December 2017 at 12:00 UTC.
.BXBT30M = USD 9,945.52
Expiry date and time is Friday, 8 December 2017 at 12:00 UTC.
.BXBT30M = USD 14,655.44
In this example we consider the contract XBT7D_U110. The strike is calculated to be USD 11,000. This is the nearest USD 250 increment to 110% of USD 9,945.52.
Assume you begin with 10 XBT in your account.
Unrealised P&L = number of contracts * (last price - entry price) = 100 * (0.0065 - 0.0065) = 0 XBT
Realised P&L = 0 XBT
Position margin = 100 * 0.0065 = 0.65 XBT
Wallet balance = deposits - withdrawals + realised P&L = 10 XBT
Available balance = wallet balance + unrealised P&L - order margin - position margin = 10 + 0 - 0 - (100 * 0.0065) = 9.35 XBT
Margin balance = wallet balance + unrealised P&L = 10 + 0 = 10 XBT
Unrealised P&L = 100 * (0.0087 - 0.0065) = 0.22 XBT
Realised P&L = 0 XBT
Position margin = 100 * 0.0087 = 0.87 XBT
Wallet balance = 10 XBT
Available balance = 10 + 0.22 - 0 - 0.87 = 9.35 XBT
Margin balance = 10 + 0.22 = 10.22 XBT
Calculations for all other dates until expiry (3, 4, 5, 6, and 7 Dec) follow the same methodology, just using different hypothetical² last prices.
Unrealised P&L = 0 XBT
Realised P&L = number of contracts * (settlement price - entry price) = 100 * (0.0249 - 0.0065) = 1.84 XBT
Position margin = 0 XBT
Wallet balance = 10 - 0 + 1.84 = 11.84 XBT
Available balance = 11.84 XBT
Margin balance = 11.84 XBT
Assume you begin with 10 XBT in your account.
Unrealised P&L = number of contracts * (last price - entry price) = 100 * (0.0087 - 0.0087) = 0 XBT
Realised P&L = 0 XBT
Position margin = 100 * 0.0087 = 0.87 XBT
Wallet balance = deposits - withdrawals + realised P&L = 10 XBT
Available balance = wallet balance + unrealised P&L - order margin - position margin = 10 + 0 - 0 - (100 * 0.0087) = 9.13 XBT
Margin balance = wallet balance + unrealised P&L = 10 + 0 = 10 XBT
Unrealised P&L = 100 * (0.0121 - 0.0087) = 0.34 XBT
Realised P&L = 0 XBT
Position margin = 100 * 0.0121 = 1.21 XBT
Wallet balance = 10 XBT
Available balance = 10 + 0.34 - 0 - 1.21 = 9.13 XBT
Margin balance = 10 + 0.34 = 10.34 XBT
Unrealised P&L = 0 XBT
Realised P&L = number of contracts * (exit price - entry price) = 100 * (0.0096 - 0.0087) = 0.09 XBT
Position margin = 0 XBT
Wallet balance = 10 + 0.09 = 10.09 XBT
Available balance = 10.09 XBT
Margin balance = 10.09 XBT
² The hypothetical price is a theoretical value calculated using a Black-Scholes model and constant parameters
(interest rate = 0, repo = 0, implied volatility = 190). It is only being used for illustrative purposes and is not a
true reflection of the actual market price at which you can buy/sell.