Define a period

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How many working days in year 1990?

Here is the detail of the calculation:

Because 1990 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 10 public holidays that do not fall during a weekend and we obtain 251 working days in 1990.

Here is the list of these 10 public holidays:

1. Jour de l'An : Monday, 1 January, 1990
2. Lundi de Pâques : Monday, 16 April, 1990
3. Fête du Travail : Tuesday, 1 May, 1990
4. Jeudi de l'Ascension : Thursday, 24 May, 1990
5. Lundi de la Pentecôte : Monday, 4 June, 1990
6. Jour de la fête Dieu : Thursday, 14 June, 1990
7. Fête de l'Assomption : Wednesday, 15 August, 1990
8. Fête de la Toussaint : Thursday, 1 November, 1990
9. Fête Nationale : Monday, 19 November, 1990
10. Jour de Noël : Tuesday, 25 December, 1990

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

1. Jour de la Sainte Dévote : Saturday, 27 January, 1990
2. Fête de l'Immaculée Conception : Saturday, 8 December, 1990