There is hereby created the treasurer of state‘s contingent fund, which shall not be a part of the state treasury. Money received by the treasurer of state that is provisional in nature or the disposition of which cannot be determined immediately shall, in accordance with rules adopted by the treasurer of state, be credited to this fund until a determination is made as to the final disposition of the money. The treasurer of state shall establish by rule the form and manner of deposits into and disbursements from the fund and the circumstances under which deposits may be made into and disbursements may be made from the fund. All income earned on money credited to this fund shall be credited to the general revenue fund.