Section 5(b) in The Employee's Compensation Act, 1923
(b)where the whole of the continuous period of service immediately preceding the accident during which the employee was in the service of the employer who is liable to pay the compensation was less than one month, the monthly wages of the employee shall be the average monthly amount which, during the twelve months immediately preceding the accident, was being earned by an employee employed on the same work by the same employer, or, if there was no employee so employed, by a workman employed on similar work in the same locality;
