Add Field Total for Date Range

Hello,

We are trying to create a field, not a report, that adds up the Principal Balance for a given month. 

Each record is a loan. So for example, the new field name would be January Funded and the field would display the total principal balance for all loans booked in January for every record.

February Funded would display the total principal balance for all loans booked in February for every record - so on and so forth.

For reference - the date field we would use is [Loan Processing Date], principal balance field is [Original Principal]

We need this in a field for several calculations we are trying to accomplish. Any ideas how we can get this to work?

TIA!

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Gelo
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