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How many working days in year 1983?

Here is the detail of the calculation:

Because 1983 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 9 public holidays that do not fall during a weekend and we obtain 251 working days in 1983.

Here is the list of these 9 public holidays:

1. Sexta-Feira Santa : пятница, 1 апрель, 1983
2. Dia da Liberdade : понедельник, 25 апрель, 1983
3. Corpo de Deus : четверг, 2 июнь, 1983
4. Dia de Portugal : пятница, 10 июнь, 1983
5. Assunção de Nossa Senhora : понедельник, 15 август, 1983
6. Implantação da República : среда, 5 октябрь, 1983
7. Todos os Santos : вторник, 1 ноябрь, 1983
8. Restauração da Independência : четверг, 1 декабрь, 1983
9. Dia da Imaculada Conceição : четверг, 8 декабрь, 1983

And here are the 4 public holidays falling on a weekend:

1. Solenidade da Santa Mãe de Deus : суббота, 1 январь, 1983
2. Páscoa : воскресенье, 3 апрель, 1983
3. Dia do Trabalhador : воскресенье, 1 май, 1983
4. Natal : воскресенье, 25 декабрь, 1983