This question is very similar to your other one for Sorting on TOP N.
These options are only available when you use the insert Summary Function (e.g. Sigma button). Formulatic summaries do not support this.
I would need to know your section architecture to tellyou if you could fix it but I hope the above explanation allows you to just add in a Summary COUNT at the correct group footer level to activate the option.
Edited by DBlank - 16 Jul 2009 at 2:24pm