It is unclear to me where you want these totals to reside. Perhaps what you need is a table of months which are loaded up from excel for the next 20 years. The key field could be a date field of the first day of the month. Then you can have a relationship back to the load record where the reference field is a formula for the first day of the month.
But I am not really understanding the business purpose of your request right now. If I understood that better I might be able to suggest other solutions.
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Mark Shnier (YQC)
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