ClarisImpact uses the Data Chart Tool to create a chart connected to its data. This connection allows you to change data without clicking into the data table. For example, click on a bar in a bar chart, and then type a new number to change the bar. Although you clicked on a bar, the number in the data table changes.
This is a useful feature, but it creates a limitation: your chart must show all of the data in the table. If you wanted your table to show four columns of information, but you only wanted three columns charted, you would see this limitation:
In the Chart menu, select Range....
Or double-click the chart, and select the Range tab.
In the Range window, you may expect to be able to specify three columns instead of four, but the Range is fixed, unchangeable.
The solution is to separate the chart from the data. You will lose the connection between the data points and the chart elements (the click-on-a-bar example, above), but you can then specify a different chart range. You can still update the chart by changing numbers in the data table, but clicking on a chart element will not select the data cell automatically.