Initial contribution to gratuity fund: deductible subject to statutory per service limits and may be paid in instalments. Contributions to an approved gratuity fund are deductible subject to a statutory per year salary based limit for initial contributions in respect of past service (effective for assessments from 1962-63); initial contributions are to be made in the year of admission but may be spread in instalments commencing that year. Approval may be granted with effect from the date the fund satisfied prescribed conditions. Deductibility requires an irrevocable trust, restricted bona fide employee membership, Indian investment and payment, trustee tax deduction, authority approval for rule changes, and reasonable contribution basis.