Does anybody know how to find the area under the curve of a trendline
(6th
degree polynomial in my case).

In general, here is one way...

Select 7 horizontal cells, and array enter the following equation:

=LINEST(Ys,Xs^{1,2,3,4,5,6},TRUE,FALSE)

I used Range Names to refer to the X & Y data located in columns.
This gives you the 7 coefficients,

In general, knowing that you equation is:
a+b*x+c*x^2+d*x^3+e*x^4+f*x^5+g*x^6

we take the integral to arrive at the following equation.

a*x+(b*x^2)/2+(c*x^3)/3+(d*x^4)/4+(e*x^5)/5+(f*x^6)/6+(g*x^7)/7

In two cells, set x to the upper limit, and lower limit of your range.
Subtract the two values to get the "Area."

--
HTH :)
Dana DeLouis
Windows XP & Office 2007


"Josh" wrote in message
...
I'm sorry about that, the browser did not change to the confirmation
screen,
so I did not realize that the question was posted. On another note, do you
know of any answers to this question?

"David Biddulph" wrote:

Please don't multipost.

Learn the difference between multiposting & crossposting:
http://www.cs.tut.fi/~jkorpela/usenet/xpost.html
--
David Biddulph

"Josh" wrote in message
...
Does anybody know how to find the area under the curve of a trendline
(6th
degree polynomial in my case).

Thanks in advance for any help.