Define a period

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How many working days in year 2064?

Here is the detail of the calculation:

Because 2064 is a leap year, it has 366 days.

Let's remove 52 saturdays and 52 sundays. It remains 262 days.

Now, let's remove 13 public holidays that do not fall during a weekend and we obtain 249 working days in 2064.

Here is the list of these 13 public holidays:

1. New Year's Day : Tuesday, 1 January, 2064
2. Coming of Age Day : Monday, 14 January, 2064
3. Foundation Day : Monday, 11 February, 2064
4. Vernal Equinox Day : Thursday, 20 March, 2064
5. Shōwa Day : Tuesday, 29 April, 2064
6. Children's Day : Monday, 5 May, 2064
7. Marine Day : Monday, 21 July, 2064
8. Mountain Day : Monday, 11 August, 2064
9. Respect-for-Aged Day : Monday, 15 September, 2064
10. Autumnal Equinox Day : Tuesday, 23 September, 2064
11. Health and Sports Day : Monday, 13 October, 2064
12. Culture Day : Monday, 3 November, 2064
13. Labor Thanksgiving Day (observance) : Monday, 24 November, 2064

And here are the 4 public holidays falling on a weekend:

1. Emperor's Birthday : Saturday, 23 February, 2064
2. Constitution Memorial Day : Saturday, 3 May, 2064
3. Greenery Day : Sunday, 4 May, 2064
4. Labor Thanksgiving Day : Sunday, 23 November, 2064