Leviticus 27:16-18

16And if a man hallow to Jehovah [part] of a field of his possession, thy valuation shall be according to what may be sown in it: the homer of barley seed at fifty shekels of silver.

17If he hallow his field from the year of jubilee, according to thy valuation shall it stand;

18but if he hallow his field after the jubilee, then the priest shall reckon unto him the money according to the years that remain, until the year of the jubilee; and there shall be a reduction from thy valuation.