For purposes of a layoff, an appointing authority shall compute the total number of seniority points for each employee subject to the layoff as follows: one point for each month of State employment; one point for each month of employment in the principal unit in which the layoff will occur; one point for each month of employment in the job series in which the layoff will occur; ten points for an eligible veteran; and two points for an eligible veteran who has a service–connected disability or is a former prisoner of war. An employee’s seniority points are the total of the points determined under subsection (a) of this section. In this section, “eligible veteran” has the meaning stated in § 7–207(c) of this article. An eligible veteran who is convicted of a crime after being discharged from or completing military service is ineligible for a credit under this section.