I have an Excel sheet (attached), with Months In col A and Sales in Column B.

I have derived values for each of the trendlines using formulae.

I also have Graphs for each trendline and the equation and RSQ(R2)

X Values in column A= Months

Y Values in column B = Sales**Now the problem is**

1. RSQs generated by excel graph for exponential and power trendlines are not matching with the computed RSQ values in F32 and G 32 cells.

2. Excel is computing RSQs of trendlines using formula - (RSQ(Known Ys,Known x's) I.e here Y is values of trendline and X is values of actual sales. That is how RSQs of Linear, Logarithmic and Polynomial Values are matching- Computed Vs. excel Graph generated.

What is the problem?

How does Excel Compute RSQ for Trendlines

is it the RSQ of Trend line vales and Actual sales?

Is there a bug in excel?

Need help!