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How many working days in year 1981?

Here is the detail of the calculation:

Because 1981 is not a leap year, it has 365 days.

Let's remove 52 saturdays and 52 sundays. It remains 261 days.

Now, let's remove 9 public holidays that do not fall during a weekend and we obtain 252 working days in 1981.

Here is the list of these 9 public holidays:

1. Solenidade da Santa Mãe de Deus : четверг, 1 январь, 1981
2. Sexta-Feira Santa : пятница, 17 апрель, 1981
3. Dia do Trabalhador : пятница, 1 май, 1981
4. Dia de Portugal : среда, 10 июнь, 1981
5. Corpo de Deus : четверг, 18 июнь, 1981
6. Implantação da República : понедельник, 5 октябрь, 1981
7. Restauração da Independência : вторник, 1 декабрь, 1981
8. Dia da Imaculada Conceição : вторник, 8 декабрь, 1981
9. Natal : пятница, 25 декабрь, 1981

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

1. Páscoa : воскресенье, 19 апрель, 1981
2. Dia da Liberdade : суббота, 25 апрель, 1981
3. Assunção de Nossa Senhora : суббота, 15 август, 1981
4. Todos os Santos : воскресенье, 1 ноябрь, 1981