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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 11 public holidays that do not fall during a weekend and we obtain 250 working days in 1981.

Here is the list of these 11 public holidays:

1. Confraternização Universal : четверг, 1 январь, 1981
2. Terça-feira de Carnaval : вторник, 3 март, 1981
3. Sexta Feira Santa ou Paixão de Cristo : пятница, 17 апрель, 1981
4. Tiradentes : вторник, 21 апрель, 1981
5. Dia do Trabalho : пятница, 1 май, 1981
6. Corpus Christi : четверг, 18 июнь, 1981
7. Independência do Brasil : понедельник, 7 сентябрь, 1981
8. Nossa Senhora Aparecida : понедельник, 12 октябрь, 1981
9. Finados : понедельник, 2 ноябрь, 1981
10. Dia do evangélico : понедельник, 30 ноябрь, 1981
11. Natal : пятница, 25 декабрь, 1981

And here is the public holiday falling on a weekend:

1. Proclamação da República Brasileira : воскресенье, 15 ноябрь, 1981