N.J. Stat. Ann. § 17:29A-5.10

In the event an excess profit is returned by an insurer in accordance with section 7 of this act and subsequent development demonstrates that an excess profit did not exist or was overstated, an "excess profit carry forward" in the amount of the excess profit refunded or the amount overstated, whichever is less, shall be established. This "excess profit carry forward" shall be applied by such insurer as a credit against future determinations of excess profits until such credit is exhausted or the expiration of a 15-year period from the date such carry forward was established, whichever occurs first.