N.J. Stat. § 27:15-1.8
On or before the thirtieth day of June following the filing of a schedule by any municipality as required pursuant to the provisions of section two hereof, there shall be disbursed to such municipality, out of the amount of State aid made available to it pursuant to the provisions of section 27:15-1 of the Revised Statutes, in accordance with such regulations as the State Highway Commissioner shall prescribe, the State's share of the cost, as shown in such schedule, for maintenance, lighting and repair of the municipal roads of such municipality.
During the month of January in the year following that in which such State aid was disbursed, such municipality shall file with the State Highway Commissioner a report, on such form as the commissioner shall prescribe. Such report shall include a statement setting forth all expenditures made by such municipality out of, or obligations incurred by it against, such State aid. In the event that any part of such State aid has not been expended for any of the aforementioned purposes, and is not required to meet obligations incurred for any of such purposes against such State aid, the State Highway Commissioner shall deduct an amount equal to such amount unexpended and not required to meet such obligations, from any amount of State aid made available to such municipality in accordance with the provisions of section 27:15-1 of the Revised Statutes and applicable to the calendar year in which the report mentioned in this paragraph is made. The State Highway Commissioner shall cause the amount so deducted to be reserved to the credit of such municipality in the same manner, and subject to the same terms, as if such municipality had requested such reservation, prior to disbursement to it of such amount, in accordance with the provisions of section thirteen of this act.
N.J.S. § 27:15-1.8