More graph types -- spc charts

Hi Carl:

Quick question (I hope): I have a data set I’m going to plot as an histogram, and I would like to superimpose on that a cumulative line. So, imagine a chart with 12 bars, then a line on top of that whose first data point = 16%, 2nd= 16% + 14% (30%), 3rd = 16% + 14% + 13% (43%), etc. The final datapoint for the line = 100%. You’ve likely seen them.

How do I go about generating a line like that? Should I hop through all the hoops on the db side to calculate all the values for the line and return two distinct datasets? or can factorypmi help me out.

Thx a bunch. David