(1) In determining whether an employer has met the requirement in 15-31-132, MCA, that they have employed 20 or fewer employees working at least 20 hours a week, the following calculation will apply:

(a) add the total hours worked and hours for which payment is made or due for reasons such as sick leave, vacation, or paid holiday by all eligible employees but do not include more than 2,080 hours for an employee;

(b) divide the total hours by 2,080; and

(c) if the result in (b) is more than 20 but less than 21, round the result down to 20.