Define a period

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How many working days in year 2004?

Here is the detail of the calculation:

Because 2004 is a leap year, it has 366 days.

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

Now, let's remove 14 public holidays that do not fall during a weekend and we obtain 248 working days in 2004.

Here is the list of these 14 public holidays:

1. New Year's Day : Thursday, 1 January, 2004
2. Coming of Age Day : Monday, 12 January, 2004
3. Foundation Day : Wednesday, 11 February, 2004
4. Shōwa Day : Thursday, 29 April, 2004
5. Constitution Memorial Day : Monday, 3 May, 2004
6. Greenery Day : Tuesday, 4 May, 2004
7. Children's Day : Wednesday, 5 May, 2004
8. Marine Day : Monday, 19 July, 2004
9. Respect-for-Aged Day : Monday, 20 September, 2004
10. Autumnal Equinox Day : Thursday, 23 September, 2004
11. Health and Sports Day : Monday, 11 October, 2004
12. Culture Day : Wednesday, 3 November, 2004
13. Labor Thanksgiving Day : Tuesday, 23 November, 2004
14. Emperor's Birthday : Thursday, 23 December, 2004

And here is the public holiday falling on a weekend:

1. Vernal Equinox Day : Saturday, 20 March, 2004