cell tower lease

We have had a least to a cell tower company for several years receiving payment monthly which is reported on 1099-MISC;

last year the lease was re-negotiated to be paid up; we are receiving the amount over 5 years;

we received a 1099-S for the full amount; where is this reported; 

for the most part, the information for 1099-S is regarding sale of property; homes; rental homes, etc.

how is this reported?