Define a period

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How many working days in year 1938?

Here is the detail of the calculation:

Because 1938 is not a leap year, it has 365 days.

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

Now, let's remove 9 public holidays that do not fall during a weekend and we obtain 251 working days in 1938.

Here is the list of these 9 public holidays:

1. Paasmaandag : Monday, 18 April, 1938
2. Hemelvaartsdag : Thursday, 26 May, 1938
3. Pinkstermaandag : Monday, 6 June, 1938
4. Nationale Feestdag : Thursday, 21 July, 1938
5. Onze-Lieve-Vrouw Hemelvaart : Monday, 15 August, 1938
6. Allerheiligen : Tuesday, 1 November, 1938
7. Wapenstilstand : Friday, 11 November, 1938
8. Koningsdag : Tuesday, 15 November, 1938
9. Tweede Kerstdag : Monday, 26 December, 1938

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

1. Nieuwjaarsdag : Saturday, 1 January, 1938
2. Dag van de Arbeid : Sunday, 1 May, 1938
3. Kerstmis : Sunday, 25 December, 1938