Define a period

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How many working days in year 1988?

Here is the detail of the calculation:

Because 1988 is a leap year, it has 366 days.

Let's remove 53 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 1988.

Here is the list of these 14 public holidays:

1. New Year's Day : Friday, 1 January, 1988
2. Coming of Age Day : Monday, 11 January, 1988
3. Foundation Day : Thursday, 11 February, 1988
4. Shōwa Day : Friday, 29 April, 1988
5. Constitution Memorial Day : Tuesday, 3 May, 1988
6. Greenery Day : Wednesday, 4 May, 1988
7. Children's Day : Thursday, 5 May, 1988
8. Marine Day : Monday, 18 July, 1988
9. Respect-for-Aged Day : Monday, 19 September, 1988
10. Autumnal Equinox Day : Friday, 23 September, 1988
11. Health and Sports Day : Monday, 10 October, 1988
12. Culture Day : Thursday, 3 November, 1988
13. Labor Thanksgiving Day : Wednesday, 23 November, 1988
14. Emperor's Birthday : Friday, 23 December, 1988

And here is the public holiday falling on a weekend:

1. Vernal Equinox Day : Sunday, 20 March, 1988