Nice explanation.....However, I dont understand one thing in your profit calculation - Why did you use 5000 to calculate the M2M (in column AA)? Also, where you have mentioned price under Buy/Sell, does that mean yo bought or sold the contract at that price?
ppandya,
Although, I have never traded commodities (spread lead & Zinc). What I understand is with every Rs. 1.00 move in your favour you gain Rs. 5000/- and so is the loss if it moves against you by Re. 1.00 hence he has taken it as 5000, for other pairs it would be different.
SHEKHAR