Hello...I am an OLAP-newbie hoping someone here can lend a hand.

I'm building a cube where one of my dimensions is composed of Year
and Period (it's not a time dimension). A year can have any number
of periods. There are four measures in the cube, but only one (Amount)
needs to have the Period be a YTD figure.

I think what I need is a calculated cell, but all I get is the dreaded
#ERR if I use the formula: Sum({YTD()},([Measures],[Amount])in the
Calculation Condition.

Can YTD be only used on time dimensions, and if so, what other solution
is there?

Thanks.