Dear Pranothi,
Manpower planning varies from one industry to another and from one company to another.
Let me give you a simple example. I understand that Oberoi Group (hospitality sector) follows a 1:2.5 ratio, i.e., for every hotel room, there should be 2.5 persons. This includes security, gardeners, gym assistants, and the General Manager of the hotel. However, others do not follow the same principle.
Manpower planning is based on the standards of your industry. First, find out those standards, and then your job will become easy. When doing manpower planning, consider employee absences due to leave (as per the statute), sickness, attrition, etc. Many companies do not make provisions for valid or invalid absences, leading other employees to end up working more. This can be the starting point of a decline in morale and motivation.
The second practice is to have some extra manpower. Later, as and when attrition occurs, you will not need to fill those vacancies.
Ok...
Dinesh V Divekar