Define a period

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How many working days in year 2009?

Here is the detail of the calculation:

Because 2009 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 8 public holidays that do not fall during a weekend and we obtain 253 working days in 2009.

Here is the list of these 8 public holidays:

1. Nieuwjaarsdag : Thursday, 1 January, 2009
2. Paasmaandag : Monday, 13 April, 2009
3. Dag van de Arbeid : Friday, 1 May, 2009
4. Hemelvaartsdag : Thursday, 21 May, 2009
5. Pinkstermaandag : Monday, 1 June, 2009
6. Nationale Feestdag : Tuesday, 21 July, 2009
7. Wapenstilstand : Wednesday, 11 November, 2009
8. Kerstmis : Friday, 25 December, 2009

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

1. Onze-Lieve-Vrouw Hemelvaart : Saturday, 15 August, 2009
2. Allerheiligen : Sunday, 1 November, 2009