Populating cells of a crosstab

Hello,

I have trouble with the following scenario:

I have a crosstab, which is populated with aggregated values per month.

- Each row represents a different customer (20002849, 20002159, ...)

- Each column is a different month (01, 02, 03, 04, ...)

My problem is that the values in the crosstab are based on open_time (=FormatDatum([INM Open time];"MM")).

When I execute the report, the crosstab is only creating values for existing data.

When I execute this query today, it will only create the columns 01 - 08 and populate the cells.

I would like that the crosstab is always creted for the whole year 01 - 12 and the default value for each cell should be 0.

Any hints are welcome!

Best regards,

Henning