The Adjutant General shall publish annually a relative rank list of all officers in the National Guard. Separate relative rank lists shall be maintained for Army National Guard professional officers by branch; all other Army National Guard officers; all Air National Guard officers; and all retired National Guard officers. The Adjutant General shall assign to each commissioned officer on the active list of the National Guard of South Carolina a number assigning to the senior officer of each grade on each list the number "one (1)" and continuing lineally thereafter in each grade on each list in order of seniority as of the effective date of the current Federal recognition in the grade held by the officer. When the effective date of Federal recognition in any given grade is the same for two or more officers, seniority shall be governed by the date of Federal recognition in the preceding grade or grades, successively and in inverse order. When two or more officers are given an original Federal recognition in any grade in the National Guard of South Carolina with the same effective date the relative rank of such officers shall be determined according to age, the older being the senior.