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How many working days in year 1977?

Here is the detail of the calculation:

Because 1977 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 6 public holidays that do not fall during a weekend and we obtain 254 working days in 1977.

Here is the list of these 6 public holidays:

1. Vendredi Saint : пятница, 8 апрель, 1977
2. Lundi de Pâques : понедельник, 11 апрель, 1977
3. Jeudi de l'Ascension : четверг, 19 май, 1977
4. Lundi de la Pentecôte : понедельник, 30 май, 1977
5. Fête nationale suisse : понедельник, 1 август, 1977
6. Jeûne genevois : четверг, 8 сентябрь, 1977

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

1. Jour de l'An : суббота, 1 январь, 1977
2. Noël : воскресенье, 25 декабрь, 1977
3. Saint-Sylvestre : суббота, 31 декабрь, 1977