34 Tex. Admin. Code § 25.301 - Calculation of Fees
All calculations of fees for service or compensation credit required by law shall be made by applying the annual percentage rate for each whole year from the ending date of the school year containing the date from which the fee is to be calculated to the beginning date of the school year in which payment in full is received by the retirement system or installment payments commence. In this section, "school year" means September 1 through August 31.
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