Define a period

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How many working days in year 1991?

Here is the detail of the calculation:

Because 1991 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 1991.

Here is the list of these 11 public holidays:

1. Jour de l'An : Tuesday, 1 January, 1991
2. Lundi de Pâques : Monday, 1 April, 1991
3. Fête du Travail : Wednesday, 1 May, 1991
4. Jeudi de l'Ascension : Thursday, 9 May, 1991
5. Lundi de la Pentecôte : Monday, 20 May, 1991
6. Jour de la fête Dieu : Thursday, 30 May, 1991
7. Fête de l'Assomption : Thursday, 15 August, 1991
8. Fête de la Toussaint : Friday, 1 November, 1991
9. Fête Nationale : Tuesday, 19 November, 1991
10. Fête de l'Immaculée Conception : Monday, 9 December, 1991
11. Jour de Noël : Wednesday, 25 December, 1991

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

1. Jour de la Sainte Dévote : Sunday, 27 January, 1991
2. Fête de l'Immaculée Conception : Sunday, 8 December, 1991