Well, Sebastian, you have to change the settings to make the data appear in the chart. By default, charts do not display data in hidden rows and columns
For changing the setting in Excel 2010:
- Click on the chart to select it, and on the Excel Ribbon > under Chart Tools > click the Design tab
- Next, click the Select Data command > click the Hidden and Empty Cells button
- Add a check mark to 'Show data in hidden rows and columns'
- Click OK, twice, to close the dialog boxes
If using Excel 2003, then follow the steps
- Click on the chart to select it, and in the Excel menu bar > click Tools | Options
- Now, on the Chart tab> remove the check mark from 'Plot visible cells only'
- Click OK, to close the dialog box