excel - Getting data off of a Graph into a table -

this yield calculator i'm working with

on left of input assay (crude oil) i'm getting in. plots on graph, has 6 horizontal lines @ temperatures cutoffs oils. wherever line crosses horizontal lines, need intersection point , put in table on top right corner of graph. right i'm guesstimating number rather getting exact one, , it's not automated. i've been trying vba pretty lost.