FORECAST function isnt producing wanted results

L

lsu-i-like

i have a graph of three points, and i use FORECAST to find a 4th poin
within those three points, but the point that FORECAST comes up wit
doesnt fall on the graph. why not and is there anything i can do
 
L

lsu-i-like

why is a polynomial trend line different from the original graph tha
excel produces
 
D

David J. Braden

Excel apparently uses Bezier curves to smooth its graphs. I *guess* it sets
up a lot of interpolation points for the purpose of charting any of its
trendlines.

If you are at all comfortable with using VBA, you might want to download my
cubic spline code (posted under Braden; watch out for the unintended line
breaks. See
http://groups-beta.google.com/group...e+author:braden&rnum=2&hl=en#bec412511748ebc9

An advanced search under the topic "cubic spline", author "Braden", group
"microsoft.public.excel.*" will yield more info.

HTH
Dave Braden
 
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