Attn: Excel gurus

[Drince88]

Actually, I was curious, so I tested - scaeagles' idea didn't quite work, but using help (I searched for "sum across worksheets") and the answer was in the first 5 or so options given) --- =SUM(Sheet1:Sheet3!f4) -- (So close to scaeagles - just without the first f4).

Refer to the same cell or range on multiple sheets
A reference that refers to the same cell or range on multiple sheets is called a 3-D reference.

Click the cell where you want to enter the function.
Type = (equal sign), enter the name of the function, and then type an opening parenthesis.
Click the tab for the first worksheet to be referenced.
Hold down SHIFT and click the tab for the last worksheet to be referenced.
Select the cell or range of cells to be referenced.
Complete the formula, and press ENTER.

(But what happens if you do just the first 19 worksheets in your workbook, and then move the 20th in the middle? May not be a concern for what you're doing, but if it's a possibility - probably should test it)