name is maurice 
I work with crystal reports 8.5 and I want to know if there is
something like trimmean available in crystal. now i have to export to
excel but it seems to me crystal can do the same but I can not find it
anywhere!

I don't think there is one, but you might be able to create one
yourself by using a formula that contains a shared variable.

You'd basically create one formula that initializes the shared
variable and put it in the report header.  The shared variable would
be an array.

Then you'd create another one in the details section that redims with
preserve the array to add another element, adds the field to the
array, then sorts it.

In the footer you'd have one final formula that creates another array
and calls the average function.  To create the second array you'd have
to figure out the top x/2 % of the array and bottom x/2% of the array
and excluse those.  It should be easy because you've sorted the array
in the details formula.

A lot of work... but it should work in the end.