Absence Management Plan

Hello everybody, I was asked to create a custom routine to calculation vacation bonuses which are given to Employee on their anniversary date. Is this field available in Lawson? If not, could I use the EMP ADJ Hire date to calculate EMP anniversary and how? Thanks in advance for your help!

Here is the specs:
1 year anniversary, 1 day = 8 vacation bonus hours
2nd year, 3 days = 24 hours
3rd year, 3 days = 32 hours
4th year, 4 days = 40 hours
5th year, 5 days = 48 hours
6th year, 6 days = 56 hours
15 -19 yrs, 1 day = 08 hours
20 - 24 yrs, 2 days = 16 hours
25 - 29 yrs, 3 days = 24 hours
30 - 34 yrs, 4 days = 32 hours
35 or more, 5 days = 40 hours