New Jersey Statutes Title 54. Taxation 54 § 4-35.1

b. (1) In the case of a county participating in the demonstration program established by section 4 of P.L.2013, c. 15 (C.54:1-104), when any parcel of real property contains any building or other structure which has been destroyed, consumed by fire, demolished, or altered in such a way that its value has materially depreciated, either intentionally or by the action of storm, fire, cyclone, tornado, or earthquake, or other casualty, which depreciation of value occurred after October 1 in any year and before May 1 of the following year, the assessor shall, upon notice thereof being given to him by the property owner prior to May 3 of that year, and after examination and inquiry, determine the value of the parcel of real property as of that May 1, and assess the same according to such value within the final tax list delivered to the county board of taxation on or before May 5 of that year.

(2) To properly capture the value of the building or structure from January 1 to the date of the depreciation of the building or structure, the assessor's final tax list shall include an improvement value that reflects the prorated value of the building or structure as of January 1 for the number of days prior to the date of the depreciation of the building or structure.