19 CAR § 12-206
(b)
(1) In order to determine the distribution to each participant, charges and fees, the Treasurer of State shall:
(i) Compute the daily rate of return of the trust for the preceding month.
(ii) The daily rate of return will be calculated as a monthly annualized yield assuming daily amortization/accretion of all fixed income securities held by the trust and any realized profits or losses; and