Define a period

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How many working days in year 2077?

Here is the detail of the calculation:

Because 2077 is not a leap year, it has 365 days.

Let's remove 52 saturdays and 52 sundays. It remains 261 days.

Now, let's remove 15 public holidays that do not fall during a weekend and we obtain 246 working days in 2077.

Here is the list of these 15 public holidays:

1. New Year's Day : Friday, 1 January, 2077
2. Coming of Age Day : Monday, 11 January, 2077
3. Foundation Day : Thursday, 11 February, 2077
4. Emperor's Birthday : Tuesday, 23 February, 2077
5. Shōwa Day : Thursday, 29 April, 2077
6. Constitution Memorial Day : Monday, 3 May, 2077
7. Greenery Day : Tuesday, 4 May, 2077
8. Children's Day : Wednesday, 5 May, 2077
9. Marine Day : Monday, 19 July, 2077
10. Mountain Day : Wednesday, 11 August, 2077
11. Respect-for-Aged Day : Monday, 20 September, 2077
12. Autumnal Equinox Day : Thursday, 23 September, 2077
13. Health and Sports Day : Monday, 11 October, 2077
14. Culture Day : Wednesday, 3 November, 2077
15. Labor Thanksgiving Day : Tuesday, 23 November, 2077

And here is the public holiday falling on a weekend:

1. Vernal Equinox Day : Saturday, 20 March, 2077