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 6 public holidays that do not fall during a weekend and we obtain 255 working days in 1988.

Here is the list of these 6 public holidays:

1. Nieuwjaar : Friday, 1 January, 1988
2. Goede Vrijdag : Friday, 1 April, 1988
3. Tweede Paasdag : Monday, 4 April, 1988
4. Hemelvaartsdag : Thursday, 12 May, 1988
5. Tweede Pinksterdag : Monday, 23 May, 1988
6. Tweede Kerstdag : Monday, 26 December, 1988

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

1. Eerste Paasdag : Sunday, 3 April, 1988
2. Koninginnedag : Saturday, 30 April, 1988
3. Eerste Pinksterdag : Sunday, 22 May, 1988
4. Eerste Kerstdag : Sunday, 25 December, 1988