The day on which the consuls took office varied throughout the Republican period. Livy's periochae report that from the year 153 onwards the consuls took office on 1 January, and not on 15 March as had been the case until then, a change that may have been caused by the Celtiberian rebellion in Hispania. According to Mommsen, the date of the Ides of March was designated as the beginning of the consular year some time between 233 and 217, although he favoured the year 222 as the most likely, given the dates of consular triumphs reported by the fasti triumphales. More recently, Hans Beck suggested plausibly that, as in the case of the new regulation of 153, there may have been a military reason for beginning the consular year on 15 March, and that this may have taken place in 218, linked to the beginning of the Second Punic War. The outbreak of the conflict may have made it advisable for the consuls to take office earlier in order to see to preliminary military actions as soon as possible, once they had completed their compulsory civil tasks in Rome. Nevertheless, the first time Livy mentions the consuls taking office on the Ides of March is in his account for the year 217, and from then on he provides the same information on a good number of occasions, which indicates that this was indeed the norm until 153.