Seniority Fast Formula needs to deduct leave of absence (LOA)

Summary:

How can we build a fast formula for Union Seniority date that deducts length of service depending on an absence type taken. Has anyone create a FF for seniority to consider leaves of absences?

Seniority Fast Formula should ensure that the time employee was on leave is not counted towards Length of Service 

Example:

• As of today, the employee has Length of Service: 1 year 1 day
• Employee goes on leave for 30 days starting today
• After 30 days, the length of service should remain 1 year 1 day because that leave does not contribute to seniority
  • Days adjusted automatically should be -30

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