Define a period

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How many working days in year 2031?

Here is the detail of the calculation:

Because 2031 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 14 public holidays that do not fall during a weekend and we obtain 247 working days in 2031.

Here is the list of these 14 public holidays:

1. New Year's Day : Wednesday, 1 January, 2031
2. Coming of Age Day : Monday, 13 January, 2031
3. Foundation Day : Tuesday, 11 February, 2031
4. Emperor's Birthday (observance) : Monday, 24 February, 2031
5. Vernal Equinox Day : Thursday, 20 March, 2031
6. Shōwa Day : Tuesday, 29 April, 2031
7. Children's Day : Monday, 5 May, 2031
8. Marine Day : Monday, 21 July, 2031
9. Mountain Day : Monday, 11 August, 2031
10. Respect-for-Aged Day : Monday, 15 September, 2031
11. Autumnal Equinox Day : Tuesday, 23 September, 2031
12. Health and Sports Day : Monday, 13 October, 2031
13. Culture Day : Monday, 3 November, 2031
14. Labor Thanksgiving Day (observance) : Monday, 24 November, 2031

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

1. Emperor's Birthday : Sunday, 23 February, 2031
2. Constitution Memorial Day : Saturday, 3 May, 2031
3. Greenery Day : Sunday, 4 May, 2031
4. Labor Thanksgiving Day : Sunday, 23 November, 2031