Define a period

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How many working days in year 2003?

Here is the detail of the calculation:

Because 2003 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 12 public holidays that do not fall during a weekend and we obtain 249 working days in 2003.

Here is the list of these 12 public holidays:

1. New Year's Day : Wednesday, 1 January, 2003
2. Coming of Age Day : Monday, 13 January, 2003
3. Foundation Day : Tuesday, 11 February, 2003
4. Vernal Equinox Day : Thursday, 20 March, 2003
5. Shōwa Day : Tuesday, 29 April, 2003
6. Children's Day : Monday, 5 May, 2003
7. Marine Day : Monday, 21 July, 2003
8. Respect-for-Aged Day : Monday, 15 September, 2003
9. Autumnal Equinox Day : Tuesday, 23 September, 2003
10. Health and Sports Day : Monday, 13 October, 2003
11. Culture Day : Monday, 3 November, 2003
12. Emperor's Birthday : Tuesday, 23 December, 2003

And here are the 3 public holidays falling on a weekend:

1. Constitution Memorial Day : Saturday, 3 May, 2003
2. Greenery Day : Sunday, 4 May, 2003
3. Labor Thanksgiving Day : Sunday, 23 November, 2003