Grouped Report with Charts

[FL_Boy]

I've got a table with three Columns
dDate, Sales, Region
1/1/11, 50, 1
2/1/11, 40, 1
3/1/11, 35, 1
1/1/11, 55, 2


2/1/11, 45, 2
3/1/11, 30, 2
1/1/11, 20, 3
2/1/11, 25, 3
3/1/11, 30, 3

I can generate a grouped report based on Region in tabular format by dragging the [Region] into the header portion of the report. I'd like to do the same with a chart. When I insert a chart into the report it uses all the data and doesn't filter it by [region]. In the detail portion of the chart, I've tried to programmatically set the rowsource of the chart using the "on format" event, but got an error.
What should I be looking at to do this?

[June7]

Put Region in a group header, not report header. Put chart in the Group header. Chart RowSource: SELECT Format([dDate],"MMM 'YY"), Sales FROM [Table1] WHERE Region=tbxRegion;

Do you need to limit the records to a specific year? Will need more WHERE criteria in the chart's RowSource.

[FL_Boy]

thanks--I though I was doing what you had suggested, but trying it one more time did the trick! It looks great.
Folks are pretty amazed to learn that access can do charts.