Hi,

I created a bar chart in Excel from the following data:

X Y
73 6.6
78 5.7
86 4.8

The SLOPE and the INTERCEPT functions returned -0.136 and 16.4448
respectively. The resulting equation is Y = -0.136X + 16.448 which seems good
enough to me.

Then I added a linear trendline to the chart. Excel displayed the following
equation: Y = -0.9X + 7.5, R ^2 =1 which is way off (and it's not a rounding
problem)!!!

The data seemed farly linear to me, how come Excel can't come up with the
right equation???

Thanks

Jan M.