K.S.A. 8-1,103

The director of vehicles shall compute apportioned registration fees for each fleet as follows: (a) Divide in-state miles by total fleet miles; (b) determine the total amount necessary under the provisions of K.S.A. 8-143 , and amendments thereto, to register each and every vehicle of a fleet for which apportioned registration is sought, based on the regular annual fees for a registration year or applicable fees for the unexpired portion of the registration year; and (c) multiply the sum obtained under subsection (b) by the percentage factor obtained under subsection (a).