Quarterly periods for the supply of electricity: without quarterly differentiation or Period I (from 1 January to 31 March), Period II (from 1 April to 30 June), Period III (from 1 July to 30 September) and Period IV (from 1 October to 31 December). ###>Périodes trimestrielles pour la fourniture d'électricité : sans différenciation trimestrielle ou Période I (du er er er