N.J. Stat. § 39:6-59
The commissioner shall, on or before the fifteenth day of October in each year, apportion the amount so certified to him among the mutual associations and stock companies writing motor vehicle liability insurance within this State or motor vehicle liability bonds, or both, in the proportion that the net premiums received by each of them for such insurance and bonds written or renewed on risks within this State during the calendar year immediately preceding, as reported to him, bears to the sum total of all such net premiums received by all mutual associations and stock companies writing such insurance or bonds, or both, within the State during such year, as so reported, and shall certify the sum so apportioned to each such mutual association and stock company on or before November fifteenth next ensuing, to the Division of Taxation in the Department of the Treasury and each such mutual association and stock company shall pay the amount so certified as apportioned to it to the said Division of Taxation on or before the thirty-first day of December next ensuing, and the sum so paid shall be paid into the State Treasury in reimbursement to the State for the expenses so paid.
N.J.S. § 39:6-59