Define a period

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How many working days in year 1988?

Here is the detail of the calculation:

Because 1988 is a leap year, it has 366 days.

Let's remove 53 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 1988.

Here is the list of these 8 public holidays:

1. Nieuwjaarsdag : Friday, 1 January, 1988
2. Paasmaandag : Monday, 4 April, 1988
3. Hemelvaartsdag : Thursday, 12 May, 1988
4. Pinkstermaandag : Monday, 23 May, 1988
5. Nationale Feestdag : Thursday, 21 July, 1988
6. Onze-Lieve-Vrouw Hemelvaart : Monday, 15 August, 1988
7. Allerheiligen : Tuesday, 1 November, 1988
8. Wapenstilstand : Friday, 11 November, 1988

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

1. Dag van de Arbeid : Sunday, 1 May, 1988
2. Kerstmis : Sunday, 25 December, 1988