I'd like to create on my Account object a rollup which sums the "total CustomObjectC amount" which have been custom_field_date in last week.
My first approach was to create a formula fields that says:
Last Week Amount = IF(Today() -7 < Custom_Field_Date__c, Amount__c,0)
and then try to roll it up, but this field doesn't appear in the list of field that can be rolled. What is the right way to solve this?