# Calculating the formula for a graph

I am trying to work out the formula used for this graph, I don't really know where to start, does anyone have any suggestions? Its a bit unclear, its showing FAT, Mach No, CIT, FWD B/P Position.

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are you trying to justify a formula for that page that is given somewhere else? Or are you trying to come up with a formula out of the blue? Are you trying to fit a set of points on that page loosely (where you formula just has to get close to your points, using regression) or exactly (where the function goes exactly through each given point)? –  Mitch Feb 10 '11 at 15:01