Define a period

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How many working days in year 1990?

Here is the detail of the calculation:

Because 1990 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 1990.

Here is the list of these 8 public holidays:

1. Nieuwjaar : Monday, 1 January, 1990
2. Goede Vrijdag : Friday, 13 April, 1990
3. Tweede Paasdag : Monday, 16 April, 1990
4. Koninginnedag : Monday, 30 April, 1990
5. Hemelvaartsdag : Thursday, 24 May, 1990
6. Tweede Pinksterdag : Monday, 4 June, 1990
7. Eerste Kerstdag : Tuesday, 25 December, 1990
8. Tweede Kerstdag : Wednesday, 26 December, 1990

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

1. Eerste Paasdag : Sunday, 15 April, 1990
2. Bevrijdingsdag : Saturday, 5 May, 1990
3. Eerste Pinksterdag : Sunday, 3 June, 1990