N.J. Stat. § 48:2-60
The assessment shall be equal to a percentage of the gross operating revenue of the public utilities under the jurisdiction of the board derived from intrastate operations during the preceding calendar year at a rate to be determined annually by the board on or before June 30 in the following manner:
The total amount appropriated to the Board of Public Utilities by law for its general purposes for its next fiscal year shall be divided by the total amount of the gross operating revenues of all public utilities under the jurisdiction of the board derived from intrastate operations during the preceding calendar year. The quotient resulting shall constitute the percentage rate of the assessment for the calendar year in which such computation is made. The total amount so assessed to any particular public utility shall not exceed 1/4 of 1% of the gross operating revenue subject to assessment hereunder of that utility derived from its intrastate operation during the preceding calendar year, except that the minimum assessment for any public utility shall be $500.00.
N.J.S. § 48:2-60