You could write some code to copy over the numbers where you enter the Xs,
but the formula to do the addition is far easier. At the end of column B,
for example: =sumif($A$1:$A4,"X",B$1:B4). In words, look for 'X' in column A
and add up the corresponding values from column B.

"Carrie" wrote:

I have values entered into a column. In the next columns over I'd like to be
able to simply enter X or another marking value so that the numbers from that
row carry over without me having to enter in the number every time I want to
use it.

Example:
A B C D
1 X X
2 X X
3 X X X
4 X

So that either the X's turn into the numbers from column A or when I sum the
values at the bottom of columns B, C, and D they add up to 6, 5, and 8
respectively. Any help?