Smooth line graph eror

[zw1ck]

So I am trying to make a smooth line graph in excel 2007. I have the points at (6.67,32), (7.78,32.1), (8.6,32.18), and (12.5,32). instead of making a smooth line with 32.18 as the maximum it puts a little bump between 32 and 32.1 with a maximum of about 32.2 so the graph has a little m in the middle. if I remove the 32.1 point (it was just an estimate to try and make the line fit better) it is smooth but it still isn't using 32.18 as the maximum which it needs to be. Is there something I'm missing here or is this just doomed to be erroneous.

And I just realized I misspelled error in the title *sigh*

 

[Asala42]

I believe that's normal excel behavior - the smoothed line is an approximation but I'm unaware of any built in options to tweak this.

Here's a link that references some example files that explore excel's logic that you might find useful
Mystery solved! The secret of Excel curved line interpolation | The Splitwise Blog