Define a period

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How many working days in year 1999?

Here is the detail of the calculation:

Because 1999 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 7 public holidays that do not fall during a weekend and we obtain 254 working days in 1999.

Here is the list of these 7 public holidays:

1. Nieuwjaarsdag : Friday, 1 January, 1999
2. Paasmaandag : Monday, 5 April, 1999
3. Hemelvaartsdag : Thursday, 13 May, 1999
4. Pinkstermaandag : Monday, 24 May, 1999
5. Nationale Feestdag : Wednesday, 21 July, 1999
6. Allerheiligen : Monday, 1 November, 1999
7. Wapenstilstand : Thursday, 11 November, 1999

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

1. Dag van de Arbeid : Saturday, 1 May, 1999
2. Onze-Lieve-Vrouw Hemelvaart : Sunday, 15 August, 1999
3. Kerstmis : Saturday, 25 December, 1999