Calculating 'Off-Contract spend'

Hi,

I noticed that in our spend reporting solution there is a "pre-calculated" measure called "off-PO Spend". When i check the details, it seems to be calculated by a formula which is sum(if(POAmount==0.0,Amount,0.0)).

I was wondering if I can self-define similar measures. What i would need is e.g. "Off-Contract spend". This should be calculated via a field in supplier master data. If supplier contract type is e.g. maintained as "Contract", then this spend should count as "Contract Spend". If supplier contrac type is not maintained, this should count as "Off-Contract spend".

Is there any way to define this?

Thanks,
Heiko