Hi
Quoting here under the explanation given in the factories rules. Please go through the same which I hope will clear your confusion:
1. The average number of workers employed daily should be calculated by dividing the aggregate number of attendance on working days (that is man days worked) by the number of working days in the year. In reckoning attendance, attendance by temporary as well as permanent employees should be counted and all employees should be included, whether they are employed directly, or under contractors. Attendance on separate shifts (e.g. night and day shifts) should be counted separately. Days on which the factory was closed for whatever cause, and days on which the manufacturing processes were not carried on should not be treated as working days partial attendance for less than half a shift on a working day should be ignored, while attendance for half a shift or more on such days should be treated as full attendance.
2. The average number of hours worked per week means the total actual hours worked by all workers during the year excluding the rest intervals but including overtime work divided by the product of total number of workers employed in the factory during the year and 52 (i.e. number of weeks in a year).
Regards
T.M. Rao