Excel graphing and trendline bug?

[ET_69]

Good afternoon.

I'm using excel 2007 to graph some data, put in a trendline, show the equation and then use that equation to generate projected results to compare against the original data.

Here is the result.  The blue curve is the actual data with trendline and resulting equation.  The red curve is the calculated data from the blue trendline equation along with its own trendline and equation.  The curves are obviously very different, as are the trendlines, but the resulting equations are identical.  Impossible.

What gives?

[#2]

This is due to the fact that the trendline's parameters are displayed rounded and as you can imagine especially the ones used for the higher factors have a large effect on the outcome. You can right-click the trendline and change the number of decimals the trendline displays.

[#3]

@Jan Karel Pieterse  Thank you, Jan!  Yes, I increased the number of decimals to 5 and the curves matched up.