On line 20 of K-1 Form 1065 , there is a code AG-Gross receipts for section 448 (c). What does that mean and where do I get these figures?

On my K-1 statement, it has 3 years of figures with the code AG for line 20:
Gross receipts for 2019-$1,634
Gross receipts for 2018-$1,103
Gross receipts for 2017-$1,160
What do I do with these figures