231.495  Retirement annuities authorized.--District school boards are authorized to purchase annuities for all school personnel with 25 or more years of creditable service who have reached age 50 and have applied for retirement under the Florida Retirement System or who have reached age 55 and have applied for retirement under plan E of the Teachers' Retirement System. No such annuity shall provide for more than the total difference in retirement income between the retirement benefit based on average monthly compensation and creditable service as of the member's early retirement date and the early retirement benefit. District school boards may also purchase annuities for members of the Florida Retirement System who have out-of-state teaching service in another state or country which is documented as valid by the appropriate school board. Such annuities may be based on no more than 5 years of out-of-state teaching service and may equal, but not exceed, the benefits that would be payable under the Florida Retirement System if credit for out-of-state teaching was authorized under that system. District school boards are authorized to invest funds, purchase annuities, or provide local supplemental retirement programs for purposes of providing annuities for school personnel. All retirement annuities shall comply with s. 14, Art. X of the State Constitution.