Determining an equation from a dataset

[Chuck Allen]

I have a data set that I would like to determine the
equation for.

I have a data set consisting of 24 months of sales. I
graphed this using a line chart so let's call this line
representing the actual data - ACTUAL LINE. On the same
chart, I graphed the first 12 months of the data and used
the TREND function to determine the next 12 months - let's
call this line of 12 months actual and 12 months trend -
TREND LINE.

I would like to determine the equation of each of the two
lines so that I can apply those equations to a similar but
different data set.

How do I determine the euqations of the two lines so that
I can apply them to another data set to predict the future
trend?

Thanks for your help!!

Chuck

 

[Tushar Mehta]

[This followup was posted to microsoft.public.excel.worksheet.functions
with an email copy to Chuck Allen.
Please use the newsgroup for further discussion.]

Use LINEST (or LOGEST) to calculate the values in a worksheet. To
learn how to use LINEST with something other than a linear equation,
see http://www.stfx.ca/people/bliengme/ExcelTips/Polynomial.htm.

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Regards,

Tushar Mehta, MS MVP -- Excel
www.tushar-mehta.com
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