N.J. Stat. § 52:18A-90.3
In any common trust fund where the income of the participating funds inures to the benefit of the participating funds, ownership in the common trust fund shall be delineated by units which shall be evidenced by certificates issued by the Director of the Division of Investment.
Any and all interest and cash dividends received by such common trust fund shall be distributed monthly to the participating funds in the proportion of the number of units owned by each such fund. The State Investment Council may, from time to time, designate as income to the participating funds, such amounts of the realized appreciation of principal to the common trust fund as it may deem prudent. Such income shall be distributed to the participating funds in the proportion of the number of units owned by each fund. The valuation of each unit in the common trust fund shall be determined in a manner to be established by regulation of the State Investment Council.
N.J.S. § 52:18A-90.3