I don't need the answers to this question, I just need an explanation of why were using the PV of $1 table to calculate these present values instead of the PVA of $1 table since the payments are received at the end of each of the years?

Determine the combined present value as of December 31,2021 , of the following four payments to be received at the end of each of the designated years, assuming an annual interest rate of 8%. (FV of $1,PV of $1,FVA of $1,PVA of $1,FVAD of $1 and PVAD of $1 ) (Use appropriate factor(s) from the tables provided. Round your final answers to nearest whole dollar amount.)