Idea benefits are driven by the financial section of an Idea as a result,  you will need to confirm if the captured Benefit Start Date is not a future date.

Should the above be correct and yet there are not benefits calculated, please confirm if the nodes on the VDT all have Actual Values MTD Actuals.

The MTD Actuals will be displayed on the VDT as follows:

If there is no Value displayed on the MTD Actual field, please edit the Node and capture the value if its a Constant Node. If it is a KPI Node confirm if the KPI has Actual captured and the KPI period is correctly set up.

Also taking into consideration that any computation with a null value the result is null.