1668/1669
For 1668/1669, the key weeks and dates were:
Week 1: 22 December to 29 December, 1668
New Year 1669, Week 2: 29 December to January 5, 1669
Legal New Year, Week 14: 23 March to 30 March, 1669
Week 52: 14 December to 21 December , 1669
Week 1668-15 to 1668-52 missing.
