Define a period

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How many working days in year 1997?

Here is the detail of the calculation:

Because 1997 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 1997.

Here is the list of these 8 public holidays:

1. Nieuwjaar : Wednesday, 1 January, 1997
2. Goede Vrijdag : Friday, 28 March, 1997
3. Tweede Paasdag : Monday, 31 March, 1997
4. Koninginnedag : Wednesday, 30 April, 1997
5. Hemelvaartsdag : Thursday, 8 May, 1997
6. Tweede Pinksterdag : Monday, 19 May, 1997
7. Eerste Kerstdag : Thursday, 25 December, 1997
8. Tweede Kerstdag : Friday, 26 December, 1997

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

1. Eerste Paasdag : Sunday, 30 March, 1997
2. Eerste Pinksterdag : Sunday, 18 May, 1997