Calculating across multiple sheets/tabs in the same workbook

[cgsweger]

I have a workbook that I update each month for one of our doctors. It contains the $$ amounts for each doctor for the previous month. What he would like to have the workbook do is average across the year tabs ( I have a sheet for 2012, 2013, etc), and give a percentage to compare that doc with the same time last year. I am just getting comfortable using Excel, let alone trying something that seems this complicated. I have no clue as to where to start. Any assistance is greatly appreciated! I've uploaded a dummy sheet to give you an idea what I'm working with.

[daffodil11]

Can you provide additional information so we can get an idea of what data you want to average?

Are you trying to show a percent margin +/- previous year? Do you want full year comparisons of each staff's YTD stats by month?

3D formulas might be helpful here, as they can reach through multiple pages assuming the data lines up the same way each time.

For example: =AVERAGE(2012:2013!B3) will average the cells in B3 on both tabs at the same time. You can even do it over greater ranges.

[cgsweger]

What we want it to do it compare Jan 2012 to Jan 2013, and eventually Jan 2014 as we add numbers for this year. He wants to compare, month to month, each year as we progress, so he can see how each are doing compared to previous years.

[cgsweger]

If I want the value to be as a percentage, how do I do that?

Thank you by the way!

[daffodil11]

In the attachment, I'm showing the difference between the average value of 2012:2013 per person, compared to 2014. It's formatted as an accounting leger, to show red for negative values.

=B4-AVERAGE(2012:2013!B4) is the formula for the first value

test%20one(1).xls