# 3D Function

Excel performs calculations in a spreadsheet but it is also possible to perform calculations across multiple worksheets, this is called 3-dimensional (3D) functions.

## What is the problem?

Say you have a workbook that contains one sheet per month. You want to create a worksheet that will synthesize all these month in a worksheet "Year".

You want to calculate the sum of the sales for the whole year.

The mistake in such cases is to select each sheet, one by one and add the cell to have a final formula that looks like this.

=January!B3+February!B3+March!B3+ ...

The formula is correct, but it's really boring to have to select each worksheet one by one.

So let's see how we can get the same result but with another technique. 💡😍

## Analyze of the structure of the workbook

If you look at the previous formula, you can noticed that we have selected the cell B3 for each worksheets

The idea is to build a formula that will read all the cell B3 through the different worksheets.

Exactly like if you have a magic eye and you can see through 😉😎

## How to build a 3D function?

Follow these steps to build a 3D formula

• Activate the cell where you want your result
• Start to write the function SUM

=SUM(

• Then, select the cell B3 in the sheet January

=SUM(Janvier!B3

• Here is the trick
1. Press the Shift key and keep it hold
2. Then select the worksheet December
3. Release the Shift key
• The formula becomes

=SUM('January:December!'B3

The symbol colon (:) between January and December means that you select all the sheets in your workbook between January to December.

• Finish by closing the parenthesis
• And press Enter.

=SUM('January:December!'B3)

## Conclusion

When you have to create a formula though many worksheets, it's easy to build a 3D function to use in your formula many cells from different worksheet.

It's easy to build and easy to read 👍😃😍