Dear Sanju,
Are you customizing a new system or you are supporting one?
You should consider T556C for counting rules. When you are entering an absence into IT2001 system can run a counting rule based on your customizing in T556C to see which conditions is applicable for this kind of absence.
By the way other relevant table is T554S for customizing absence and attendance quota types. There are some others but the most important are these.
Cheers,
Omid
