Hi Lynne,
I have attached a screen shot of what I have done. I have a table of Invoices and I used fields Dates and Amounts. First, in your bar chart report, make a Numeric report formula (named 'month group') =Month([Date]). Use 'month group' as category label on x-axis, and group by equal values. Also note it is used for sorting low to high (so 1 =January, 2 = February, etc.). I used the summed invoice amount as the data values on the y axis, the series is the invoice Date, grouped by year. Hopefully you can apply this to your own chart.
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Lisa Sell
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