Section 90(2)(b) in Orissa State Financial Corporation (Staff) Regulations, 1975
(b)(i)In respect of the first sixty days of the maternity leave the average monthly pay earned during twelve complete months preceding the month in which the leave commences.(ii)thereafter the average monthly pay earned during the 36 complete months or actual number of complete months whichever is less, preceding the month in which the leave commences.(iii)A female employee may be granted leave of any other kind admissible to be in combination with or in continuation of maternity leave if the request for its grant is supported by sufficient medical certificate.