(c) in other cases[ including cases in which it is not possible for want of necessary information to calculate the monthly wages under clause (b)]], the monthly wages shall be thirty times the total wages earned in respect of the last continuous period of service immediately preceding the accident from the employer who is liable to pay compensation, divided by the number of days comprising such period. 3[ Explanation.-- A period of service shall, for the purposes of 4[ this 5[ section]] be deemed to be continuous which has not been interrupted by a period of absence from work exceeding fourteen days. 6[