Define a period

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How many working days in year 1965?

Here is the detail of the calculation:

Because 1965 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 7 public holidays that do not fall during a weekend and we obtain 254 working days in 1965.

Here is the list of these 7 public holidays:

1. Nieuwjaarsdag : Friday, 1 January, 1965
2. Paasmaandag : Monday, 19 April, 1965
3. Hemelvaartsdag : Thursday, 27 May, 1965
4. Pinkstermaandag : Monday, 7 June, 1965
5. Nationale Feestdag : Wednesday, 21 July, 1965
6. Allerheiligen : Monday, 1 November, 1965
7. Wapenstilstand : Thursday, 11 November, 1965

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

1. Dag van de Arbeid : Saturday, 1 May, 1965
2. Onze-Lieve-Vrouw Hemelvaart : Sunday, 15 August, 1965
3. Kerstmis : Saturday, 25 December, 1965