For 1973, the basis for calculating the variations referred to in Article 3 (3) of the Decision of 21 April 1970 shall be:
Don bhliain 1973, glacfar leo seo a leanas mar bhonn chun na hathruithe a ríomh a dtagraítear dóibh in Airteagal 3(3) de Chinneadh an 21 Aibreán 1970: