I can calculate a Running Sum in Pivot Tables. I can also insert a column
showing what percentage of the column total each line represents. However, I
can't work out how to show the running total %. My data is sorted so that
the largest value is at the top of the table. This represents 20% of the
total for that category i.e. the subtotal. The next row accounts for 14% of
the total. So, what I'd like to see is a column showing a cumulative %
against this second row of 34%. As we move down the table the percntage will
move towards 100%. After the subtotal the running % total will start again
from zero.

Can anybody help please?