Define a period

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How many working days in year 1989?

Here is the detail of the calculation:

Because 1989 is not a leap year, it has 365 days.

Let's remove 52 saturdays and 53 sundays. It remains 260 days.

Now, let's remove 6 public holidays that do not fall during a weekend and we obtain 254 working days in 1989.

Here is the list of these 6 public holidays:

1. Goede Vrijdag : Friday, 24 March, 1989
2. Tweede Paasdag : Monday, 27 March, 1989
3. Hemelvaartsdag : Thursday, 4 May, 1989
4. Tweede Pinksterdag : Monday, 15 May, 1989
5. Eerste Kerstdag : Monday, 25 December, 1989
6. Tweede Kerstdag : Tuesday, 26 December, 1989

And here are the 4 public holidays falling on a weekend:

1. Nieuwjaar : Sunday, 1 January, 1989
2. Eerste Paasdag : Sunday, 26 March, 1989
3. Koninginnedag : Saturday, 29 April, 1989
4. Eerste Pinksterdag : Sunday, 14 May, 1989