Determine missing points of plotted curve.

Question

I have a scientific study with charts as the one in the image. They made a curve to merge data from different studies and methods... using the equations in picture.

I have access to the resulted data points.

Now, from there, left column, there are the intervals of MET minutes. I would like to understand if there is any more precise formula, besides the rule of three :), to calculate missing points... let's say, to calculate what is the risk associated to breast cancer (second column), for someone who is doing 2500 MET-minutes per week (column 1).

This equation would be used in javascript / computer program to calculate data according to this table.

Thanks.