N.J. Stat. § 34:15-37
"Wages," when used in this chapter shall be construed to mean the money rate at which the service rendered is recompensed under the contract of hiring in force at the time of the accident. Board and lodging when furnished by the employer as part of the wages shall be included and valued at $25.00 per week, unless the money value of such advantages shall have been otherwise fixed by the parties of the time of hiring. Where prior to the accident, the rate of wages is fixed by the output of the employee, the daily wages shall be calculated by dividing the number of days the worker was actually employed into the total amount the employee earned during the preceding 6 months, or so much thereof as shall refer to employment by the same employer. When the rate of wages is fixed by the hour, the daily wage shall be found by multiplying the hourly rate by the customary number of working hours constituting an ordinary day in the character of the work involved. In any case the weekly wage shall be found by multiplying the daily wage by the customary number of working days constituting an ordinary week in the character of the work involved; provided, however, if the employee worked less than the customary number of working days constituting an ordinary week in the character of the work involved, the weekly wage for the purposes of compensation under provisions of R.S. 34:15-12a only shall be found by multiplying the hourly rate by the number of hours of work regularly performed by that employee in the character of the work involved. Gratuities, received regularly in the course of employment from other than the employer, shall be included in determining the weekly wage only in those cases where the employer or employee has kept a regular daily or weekly record of the amount of gratuities so received. In such cases the average weekly amount of gratuities over a period of 6 months, or for the entire time of employment, whichever period is less, shall be added to the fixed weekly wage to determine the employee's total weekly wage. If no such record has been kept, then the average amount of the weekly gratuities shall be fixed by the judge of compensation or the referee hearing the matter.
N.J.S. § 34:15-37