sumif alternative for formula

Hello

I am trying to do a formula for a calculated meaure that look something like:

sum(MeasureA for DimensionX='01')/sum(MeasureB for DimensionX='01')

I see i can use Sum({Sales}) ForAllExcept [{Product}] as in the user guide but I can not specify the Value in the Dimension. Also saw Runningsum but still not what i need

Any suggestions ?

Kind Regards

Hector