Any teacher who was sixty-five years of age at retirement and who is eligible to receive or who is receiving benefits under former chapter 15-39 may receive benefits which are not less than:

1.    Six dollars per month per year of teaching to twenty-five years.

2.    Seven dollars and fifty cents per month per year of teaching over twenty-five years. Teachers, superintendents, assistant superintendents, principals, assistant principals, special teachers, supervisors of instruction and other supervisors, presidents, deans, school librarians, and registrars employed by any state institution under the supervision and control of the state board of higher education and any person employed in teaching as lay faculty in a nonpublic school are not eligible for the minimum benefits provided by this section. As used in this section, the term “lay faculty” means any person who teaches elementary or high school students in a nonpublic school, and is neither a member of an ecclesiastical order or religious house, nor an ordained member of the clergy.

A teacher who retired at any time prior to sixty-five years of age is entitled to benefits not less than the minimum benefits established by this section reduced to the actuarial equivalent of the benefit credits earned to the date of early retirement.