Supplier Contract Management module - calculation of contract variances

My customer is using SCMT v9.1 for authoring functionality.

Is there anywhere in the system (with using delivered functionality) that it can calculate contract amount variances ?  I can't find anywhere or I missed anything.

The customer mentioned that in there old system (lecacy system), where there is a variance amount to contract document, they can just enter the new amount and the system can calculate the variance between old amount and the new amount) and this is very important for them to know the variance.  They just wonder how they can get this in the PeopleSoft Supplier Contract Management system with using delivered functionality. Currently, in the SCMT, they use contract activities to record this variance "manually" which is not they way it should be.