I downloaded the loan amortization schedule from MSO Online (the one with 4
1/2 stars rating on 889 votes).

It is using IF functions with "Values_Entered" and "Last_Row" as
logical_test values. I cannot determine from where these values are
determined. They do not show in the list of named ranges, there are no hidden
worksheets, there are no macros defined, etc. I do not believe these are
Excel reserved words.

Can anyone tell me about this implementation? Thank you in advance.