(1) A reduced incentive payment shall be made to any municipality having in its employ a qualified city street superintendent for only a portion of the calendar year preceding the year in which the payment is made. Such reduced payment shall be in the proportion of the amounts listed in section 39-2513 as the number of full months such a qualified person was employed is of twelve.
(2) Any municipality that contracts with a consulting engineer or engineering firm to perform the duties outlined in section 39-2512 rather than employing a qualified city street superintendent shall be entitled to an incentive payment as provided in section 39-2513.
(3) Any municipality that contracts with another municipality or county for the employment of a qualified city street superintendent as provided in section 39-2114, shall be entitled to the incentive payment provided in section 39-2513 or the reduced incentive payment provided in subsection
(1) of this section.