5N.I.Any question arising under this Agreement, whether as to the amount of any adjustments necessary in the determination of net costs in Great Britain and in Northern Ireland for the purposes of article 1 of this Agreement, or of any contribution payable under article 2, or otherwise, shall, in default of agreement between the Commissioners of Her Majesty's Treasury and the Ministry of Finance for Northern Ireland, be determined by the Joint Exchequer BoardF1, whose decision shall be final.