afterword,
Thanks for the suggestions. I like the idea of using the data filter to select between time periods. Wish I knew JSL or Flash. If I can find a JSL code example to control the data filter, I might be able to modify it with a little trial and error to meet my purposes.
I really should have described my need better - my bad, I simplified my description way too much. So here's what I'm really after. Imagine your top 10 customers across the x axis. The bar for each customer would represent a total amount of business (could be quantity or $) on the y-axis, with the bar segments defining different product lines, for example 10 different product lines. So a single chart shows you which customers have the highest impact on your business, and which products they buy. You can also tell if there is a difference in the product mix by customer. But businesses change over time, so introducing a time element gives you multiple pieces of data. Which customers are growing or shrinking, which product line is growing by customer, whether all customers are shifting to the same products or different ones. You can also determine if there are groupings of customers (going up the same, shifting to the same products, etc. ) This is why I thought a bar chart would be good. Customer position would be fixed, and business managers could see how the revenue and product mix is shifting and where. So with this many variables, a line chart would get too cluttered.