Define a period

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How many working days in year 2005?

Here is the detail of the calculation:

Because 2005 is not a leap year, it has 365 days.

Let's remove 53 saturdays and 52 sundays. It remains 260 days.

Now, let's remove 14 public holidays that do not fall during a weekend and we obtain 246 working days in 2005.

Here is the list of these 14 public holidays:

1. New Year's Day (observance) : Monday, 3 January, 2005
2. Coming of Age Day : Monday, 10 January, 2005
3. Foundation Day : Friday, 11 February, 2005
4. Shōwa Day : Friday, 29 April, 2005
5. Constitution Memorial Day : Tuesday, 3 May, 2005
6. Greenery Day : Wednesday, 4 May, 2005
7. Children's Day : Thursday, 5 May, 2005
8. Marine Day : Monday, 18 July, 2005
9. Respect-for-Aged Day : Monday, 19 September, 2005
10. Autumnal Equinox Day : Friday, 23 September, 2005
11. Health and Sports Day : Monday, 10 October, 2005
12. Culture Day : Thursday, 3 November, 2005
13. Labor Thanksgiving Day : Wednesday, 23 November, 2005
14. Emperor's Birthday : Friday, 23 December, 2005

And here are the 2 public holidays falling on a weekend:

1. New Year's Day : Saturday, 1 January, 2005
2. Vernal Equinox Day : Sunday, 20 March, 2005