Leviticus 25:14-16

14If you make a sale, moreover, to your friend or buy from your friend’s hand, 1you shall not wrong one another.

15Corresponding to the number of years after the jubilee, you shall buy from your 2friend; he is to sell to you according to the number of years of crops.

163In proportion to the 4extent of the years you shall increase its price, and in proportion to the fewness of the years you shall diminish its price, for it is a number of crops he is selling to you.