Define a period

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How many working days in year 1970?

Here is the detail of the calculation:

Because 1970 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 11 public holidays that do not fall during a weekend and we obtain 250 working days in 1970.

Here is the list of these 11 public holidays:

1. Jour de l'An : Thursday, 1 January, 1970
2. Jour de la Sainte Dévote : Tuesday, 27 January, 1970
3. Lundi de Pâques : Monday, 30 March, 1970
4. Fête du Travail : Friday, 1 May, 1970
5. Jeudi de l'Ascension : Thursday, 7 May, 1970
6. Lundi de la Pentecôte : Monday, 18 May, 1970
7. Jour de la fête Dieu : Thursday, 28 May, 1970
8. Fête de la Toussaint : Monday, 2 November, 1970
9. Fête Nationale : Thursday, 19 November, 1970
10. Fête de l'Immaculée Conception : Tuesday, 8 December, 1970
11. Jour de Noël : Friday, 25 December, 1970

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

1. Fête de l'Assomption : Saturday, 15 August, 1970
2. Fête de la Toussaint : Sunday, 1 November, 1970