Currency field doesn't rollup

[jimgeo]

I have an entity with a currency attribute that i want to rollup in the parent entity.  The field doesn't show any values even if I press the recalculate button, but I'm able to rollup a count value for a different attribute in the same entity for transactions in the same child table without any problem.  Any one knows what is going on here?

[DavidJennaway]

One possible cause is if either the child or the parent record doesn't have a value in the currency (transactioncurrnecyid) field. If the currency is only set on the child record, you can create a simple workflow to copy the currency from the child record to the parent record