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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 10 public holidays that do not fall during a weekend and we obtain 252 working days in 1980.

Here is the list of these 10 public holidays:

1. Capodanno : вторник, 1 январь, 1980
2. Lunedì di Pasqua : понедельник, 7 апрель, 1980
3. Anniversario Liberazione : пятница, 25 апрель, 1980
4. Festa del lavoro : четверг, 1 май, 1980
5. Festa della Repubblica Italia : понедельник, 2 июнь, 1980
6. Festa di San Giovanni : вторник, 24 июнь, 1980
7. Ferragosto o Assunzione : пятница, 15 август, 1980
8. Immacolata Concezione : понедельник, 8 декабрь, 1980
9. Santo Natale : четверг, 25 декабрь, 1980
10. Santo Stefano : пятница, 26 декабрь, 1980

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

1. Epifania : воскресенье, 6 январь, 1980
2. Ognissanti o Tutti i Santi : суббота, 1 ноябрь, 1980