Provisions of existing laws to the contrary notwithstanding, all revenues as are not needed to meet current operational expenses under this Title shall be accumulated in a fund to be known as the State Insurance Fund, which shall be used exclusively for payment of the benefits under this Title, and no amount thereof shall be used for any other purpose. All amounts accruing to the State Insurance Fund, which is hereby established in the SSS and GSIS, respectively, shall be deposited with any authorized depository bank approved by the Commission, or invested with due and prudent regard for the liquidity needs of the System.