I have a column of data with percentages of the total in the next column. I
now want to add a third column that shows the cumulative percentage of the
total. Something like:
1 2 3
A 10 10% 10%
B 20 20% 30%
C 30 30% 60%
D 40 40% 100%

What formula should I use to calculate the values for the third column?

Thanks for your help.
--
David