Hi. I'm looking for help with how to calculate weighted average profit
margin.  Basically, in an Excel spreadsheet, column A contains Sales
numbers and column B contains Profit Margin % for each of those sales
numbers. I need the weighted average profit margin for all sales
combined.

Sales    profit
$100     25%
$500     15%
$300     10%

In column C (on another unused column) calculate the profit for each sales.

=A2*B2
etc.

Then use this formula to calculate average profit margin:

=SUM(C2:C4)/SUM(A2:A4)

or without using column C use this formula:

=SUMPRODUCT(A2:A4,B2:B4)/SUM(A2:A4)

Regards,
Per

"mar" <marzracing@gmail.com> skrev i meddelelsen 
news:35c905df-df90-48c4-9000-7d8f404b2601@o3g2000vbo.googlegroups.com...
> Hi. I'm looking for help with how to calculate weighted average profit
> margin.  Basically, in an Excel spreadsheet, column A contains Sales
> numbers and column B contains Profit Margin % for each of those sales
> numbers. I need the weighted average profit margin for all sales
> combined.
>
> Sales    profit
> $100     25%
> $500     15%
> $300     10% 

Your total profit was: 100*25%  + 500*15%  + 300*10% = 25 + 75 + 30 = 130
Your total sales where 900, so %profit is 130/900 = 14.4%

If you data starts with "Sales" in A1, the sales values in A2:A4 and the 
margins in B2"B4
then this formula gives you the correct result
=SUMPRODUCT(A2:A4,B2:B4)/SUM(A2:A4)

best wishes
-- 
Bernard Liengme
Microsoft Excel MVP
http://people.stfx.ca/bliengme

"mar" <marzracing@gmail.com> wrote in message 
news:35c905df-df90-48c4-9000-7d8f404b2601@o3g2000vbo.googlegroups.com...
> Hi. I'm looking for help with how to calculate weighted average profit
> margin.  Basically, in an Excel spreadsheet, column A contains Sales
> numbers and column B contains Profit Margin % for each of those sales
> numbers. I need the weighted average profit margin for all sales
> combined.
>
> Sales    profit
> $100     25%
> $500     15%
> $300     10% 

ok got it.
thanks all!