When you pull up the margin on TOS and click explain margin it shows the 10% down number (how much you would be down) and the 6% up number as calculation. Keep in mind that the numbers are based on current assumptions so if vol jumps the calculation changes and the margin goes up. Which means if we go down 2% margin may not be the number originally quoted (if vol goes up for example). Of course time going by impacts margin too.
If you PM me your phone number, I can call you and walk you though how to use the OCC PM calculator, but it won't help you. Every broker has house rules and you need to include them. The OCC tool is fast and easy once you get accustom to using it. 1245