Parmigiani Fleurier presents its first annual calendar. The new manufacture calibre, the automatic PF 331, automatically takes into account the length of the months of 30 and 31 days. Only one correction needs to be made per year, in the non-leap year month of February. In leap years, the date displays 29 February and automatically changes to 1 March. The Tonda Annual Calendar is offered in white or pink gold and on the silver-plated or anthracite dial, it displays the date retrograde on an arc of a circle positioned on the flange; the day of the week and the month are displayed at 9 and 3 o'clock respectively. The phases of the moon, at 6, require only one correction every 120 years, reducing the gap between a classical lunar cycle and the actual lunar cycle.
