Every local board of education may adopt, as to assistant or associate superintendents not paid out of State funds, a salary schedule similar to the State salary schedule, but it likewise shall recognize a difference in salaries based on different duties, training, experience, professional fitness, and continued service in the same school system; but if any local board of education shall fail to adopt such a schedule, the State salary schedule shall be in force.
N.C. Gen. Stat. § 115C-273