Logarithmic curve formulas in charts and LOGEST fx values?

[Guest]

(Preface: I am not a math genius so I may be doing something way wrong)

I am trying to calculate values for a curve using the LOGEST fx, but the
numbers are not agreeing with the formula provided by the logarithmic curve
formulas in a chart of the data (nor by the 'eyeball' method). Any thoughts?

 

[Niek Otten]

Hi Rich,

How could we possibly know if you don't give us:

Values input to the formulas,
The formulas,
The results of the formulas,
What you expected,
What the eyeball expectations were
?

 

[Niek Otten]

Don't hesitate to post again (in this same thread) with some more details

 

[Mike Middleton]

Rich -

I am trying to calculate values for a curve using the LOGEST fx, but the
numbers are not agreeing with the formula provided by the logarithmic
curve formulas in a chart of the data (nor by the 'eyeball' method). Any
thoughts? <

Two thoughts:

(1) LOGEST is appropriate for an exponential trendline, not for the
logarithmic trendline.

(2) Be sure you're using an XY (Scatter) chart type, not a Line chart type.

- Mike
www.mikemiddleton.com

 

[Jerry W. Lewis]

http://groups.google.com/group/microsoft.public.excel.charting/msg/f3d0f2172c25a661

Jerry