Leviticus 27:17-19

27:17 If he consecrates his field in the jubilee year, the conversion value will stand, 27:18 but if he consecrates his field after the jubilee, the priest will calculate the price for him according to the years that are left until the next jubilee year, and it will be deducted from the conversion value. 27:19 If, however, the one who consecrated the field redeems it, he must add to it one fifth of the conversion price and it will belong to him.