Number of member per group

Good morning.

I search a method for have the number of member of a group and place in the header pannel of the forum.

Can you help me, please ?

Exemple : The group Psychopath have 7 membres, I note this in the header with the other group, but I will wish a function for make auto.

Thanks in advance.

Bump (yes it's an old message but, I search that)