summary of average and total in crosstab

[curious]

I have a crosstab with totals and average numbers. So when I choose to add a summary to this crosstab I want the totals to be totaled. However, an average of the average-numbers should be calculated.

I choosed to unlock the report and add calaculated item to the crosstab node. This seems not to be the right way, because nothing is displayed in this node.

How do I solve this problem.

My apologizes for my abominable knowledge of the english language.