Hereafter minimum annual salaries and compensation shall be paid to police officers and policemen, in incorporated cities of this state, in accordance with the following schedule: in incorporated cities having more than 500,000 population, police officers and policemen with more than 3 years police service shall receive an amount not less than $2,640.00 per year; in incorporated cities having a population of more than 75,000 but not exceeding 500,000, police officers and policemen with more than 3 years police service shall receive not less than $2,000.00 per year; in incorporated cities having a population of more than 25,000 but not exceeding 75,000, police officers and policemen with more than 2 years police service shall receive not less than $1,900.00 per year; in incorporated cities having a population of more than 12,500 but not exceeding 25,000, police officers and policemen with more than 2 years police service shall receive not less than $1,800.00 per year; in incorporated cities having a population of more than 5,000 but not exceeding 12,500, police officers and policemen with more than 1 year police service shall receive not less than $1,700.00 per year.

     The foregoing schedule shall apply to all incorporated cities of this state, except where incorporated cities having more than 40,000 population adjoin or lie within the boundaries of an incorporated city that has more than 500,000 population. In this case police officers and policemen of the smaller city and having 3 or more years police service shall receive not less than $2,640.00 per year.

     The last federal decennial census or any federal decennial census hereafter taken shall be used in ascertaining the size of the city for the purpose of conforming with the foregoing schedules.

     This act shall not apply to persons engaged in part time, emergency or special police service or to any person not actively engaged in said service.