OLAP cube question

[Simon Dullingham]

I'm trying to define an s-curve as an analyzer view, but I want the curve to
be in %, not in raw hour. The current calculation that I am using is

Sum(PeriodsToDate([Time].[All]),[Work])

This gives me the total number of hours in each period (month/quarter/year).

But what I want to do is have some thing like

Sum(PeriodsToDate([Time].[All]),[Work])/[total work]

Does anyone have any suggestions?

Thanks,
Simon