Open margin fraction (OMF)

OMF, or open margin fraction, is calculated as:

min(total_value, collateral) / total_open_position_notional

where total_value is collateral + unrealized_pnl

and total_open_position_notional sums all your open positions, as well as what your open positions would be if all your open orders were to be filled. If you notice that you are hitting your leverage limit earlier than you expect, please check to ensure you don't have open orders -- these will affect your OMF.