Thank you gebobs, and you are right, that didn't produce meaningful results. Honestly the values that resulted made no sense to me. I take it that method replaces the existing values with something else. I don't want to replace anything, I need the original values to stay as they are. Then I need one new column that shows a running cumulative total from row to row.

I don't understand how Excel can do any running total, I've never seen it work. Would be very curious if someone has an example where the original values aren't altered?

I suspect it's not possible because the method - a calculated field? (I've struggled with them and not come up with anything) - practically speaking, has to add the value from one row to a calculated value from the row above. Where the formula on every row is different from the formula on every row above and below. How could that even be possible in Excel.

Yet, lots of experts claim this can be done. So I would like to not give up yet. Show me please!