I am looking for a program that calculates margins requirements and puts them on a chart like the one below. I trade credit spreads on the e-minis and even though the index does not touch the short side of my spread I will start getting margin calls before it comes close to it. Depending on how many contract I have the margin calls will start even further away from the shorts. I put on this graphic below an example of what I would like to see a program do. Does one exist yet? I hope my explanation is clear for everyone to understand.