Select Data Range - how to handle adding new results

[Shane Gannon]

I use Google Spreadsheets to record the results of a monthly competition. In one sheet I record the results. Then I use Pivot table sheets to separate the results into different categories. Finally I use a line chart to graph the results with a separate chart for each category.

A categories data will look like

              Date_1 Date_2 Date_3 ......

Name_1    500      400      500    ......

Name_2    550      525      555    ......

Name_3    300      300      300    ......

Name_4    500      400      200    ......

For each new competition I'll be adding new dates and new names.

As far as I can see this means I'll need to update all the chart's Select Data Range each month. How can I avoid that?

I'd prefer to enter the results in the sheet and have them automatically propagate. i.e. To the Pivot tables (which they do) and the charts (which they don't because the range is incorrect).