Define a period

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How many working days in year 1968?

Here is the detail of the calculation:

Because 1968 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 1968.

Here is the list of these 13 public holidays:

1. New Year's Day : Monday, 1 January, 1968
2. Coming of Age Day : Monday, 8 January, 1968
3. Foundation Day (observance) : Monday, 12 February, 1968
4. Vernal Equinox Day : Wednesday, 20 March, 1968
5. Shōwa Day : Monday, 29 April, 1968
6. Constitution Memorial Day : Friday, 3 May, 1968
7. Children's Day (observance) : Monday, 6 May, 1968
8. Marine Day : Monday, 15 July, 1968
9. Respect-for-Aged Day : Monday, 16 September, 1968
10. Autumnal Equinox Day : Monday, 23 September, 1968
11. Health and Sports Day : Monday, 14 October, 1968
12. Culture Day (observance) : Monday, 4 November, 1968
13. Emperor's Birthday : Monday, 23 December, 1968

And here are the 5 public holidays falling on a weekend:

1. Foundation Day : Sunday, 11 February, 1968
2. Greenery Day : Saturday, 4 May, 1968
3. Children's Day : Sunday, 5 May, 1968
4. Culture Day : Sunday, 3 November, 1968
5. Labor Thanksgiving Day : Saturday, 23 November, 1968