The duty to be maintained on crude oils shall not, however, be such as to result in an increase of more than 5 per cent in the difference existing on 1 January 1957 between the duties on crude oils and those on the derivatives referred to above.
An dleacht atá le coimeád i bhfeidhm ar olaí amha, áfach, ní dleacht í a thabharfaidh go mbeidh nios mó ná 5 % de mhéadú sa difríocht a bhí ann an 1 Eanáir 1957 idir na dleachtanna ar olaí amha agus na dleachtanna ar na díorthaigh dá dtagraítear thuas.