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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. Solenidade da Santa Mãe de Deus : вторник, 1 январь, 1980
2. Sexta-Feira Santa : пятница, 4 апрель, 1980
3. Dia da Liberdade : пятница, 25 апрель, 1980
4. Dia do Trabalhador : четверг, 1 май, 1980
5. Corpo de Deus : четверг, 5 июнь, 1980
6. Dia de Portugal : вторник, 10 июнь, 1980
7. Assunção de Nossa Senhora : пятница, 15 август, 1980
8. Restauração da Independência : понедельник, 1 декабрь, 1980
9. Dia da Imaculada Conceição : понедельник, 8 декабрь, 1980
10. Natal : четверг, 25 декабрь, 1980

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

1. Páscoa : воскресенье, 6 апрель, 1980
2. Implantação da República : воскресенье, 5 октябрь, 1980
3. Todos os Santos : суббота, 1 ноябрь, 1980