Employees in the classified service, and employees in the unclassified
service whose employment is covered by collective negotiation agreements
which provide for longevity payments, shall be entitled to longevity
payments to the extent and in the manner provided in such agreements.
Other employees in the unclassified service shall be entitled
to receive, in addition to their regular salary, longevity pay in
the amount of 1 1/2% of base salary for each completed four years
of service, to a maximum of 7 1/2% of base salary, such longevity
payments to become due, or to be appropriately increased, on the first
day of the month following the month in which the employee's anniversary
date of employment occurred.