Pawukon calendar

The Pawukon is a 210-day calendar that has its origins in the Hindu religion in Bali, Indonesia. The calendar consists of 10 different concurrent weeks of 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 days. On the first day of the year it is the first day of all the ten weeks. Because 210 is not divisible by 4, 8, or 9, extra days must be added to the 4, 8, and 9 day weeks.