a) eight days for every twelve months of continuous service with the same employer if he has been employed by that employer for a period of less than two years; (b) twelve days for every twelve months of continuous service with the same employer if he has been employed by that employer for a period of two years or more but less than five years; and (c) sixteen days for every twelve months of continuous service with the same employer if he has been employed by that employer for a period of five years or more, itz prorated calculation right.