Hi,
I have a set of data, 100 x-values with corresponding y-values. Only about every third of the y's have a value, but by letting excel interpolate the graph, I can see how the graph should look like.

My questions are:
1. Can excel give me the formula to the graph it has drawn? Something like: "Show Equation"?

2. Is there a way to find out the y-value to a corresponding x-value? The graph has no standard-form, ie. it's not a parabel, so I don't know if I can use "trend" or "forecast"? The form of the graph is highly irregular, but excel managed to draw the graph, so it must know all it's y-values?

Please ask if anything is badly explained.

Thanks, perolav