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How many working days in year 1980?

Here is the detail of the calculation:

Because 1980 is a leap year, it has 366 days.

Let's remove 52 saturdays and 52 sundays. It remains 262 days.

Now, let's remove 6 public holidays that do not fall during a weekend and we obtain 256 working days in 1980.

Here is the list of these 6 public holidays:

1. Jour de l'An : вторник, 1 январь, 1980
2. Vendredi Saint : пятница, 4 апрель, 1980
3. Fête du Travail : четверг, 1 май, 1980
4. Jeudi de l'Ascension : четверг, 15 май, 1980
5. Fête nationale suisse : пятница, 1 август, 1980
6. Noël : четверг, 25 декабрь, 1980

And here is the public holiday falling on a weekend:

1. Indépendance : суббота, 1 март, 1980