149. Where under the foregoing provisions of this chapter there is made in any year by the Federation to a Federated State any payment or distribution of, or calculated by reference to, the net proceeds of any duty or tax, the value in and for that year of any privilege or immunity enjoyed by that State in respect of any former or existing source of revenue from a similar duty or tax or from goods of the same kind, being a privilege or immunity which has not been otherwise taken into account shall, if and in so far as the Act of the Federal Legislature under which the payment or distribution is made so provides, be set off against the payment or distribution.
