Thanks all for your quick assistance!!

I ended up with:

CONVERT(INT, 100 * (CASE EXPECTEDDURATION WHEN 0 THEN 0 ELSE 1.0 END - CONVERT(FLOAT,

(dbo.fn_GetWorkingDays(TASKSTARTDATE, GetDate())* 8)) / CONVERT(FLOAT, CASE

EXPECTEDDURATION WHEN 0...

Ok, I will dive into the CASE thingy to see if that will help me.

The 'business' is our team. We are now using a couple of our own web interfaces...