Formula field not populating for some records

I have a formula field that subtracts one other formula field:

"Company 1 Total Fees" - "Company 2 Total Fees" to get "Company 2 Savings"

Both "Total Fees" fields are formula fields and have several other fields calculated within the record. 

For some reason, only about 2% of the "Company 2 Savings" fields have values even though all "Total Fees" fields are populated.

Can't figure out why this is happening. Anyone have an idea?

Thank you!

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Matt Hartman
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