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How many working days in year 1987?

Here is the detail of the calculation:

Because 1987 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 10 public holidays that do not fall during a weekend and we obtain 251 working days in 1987.

Here is the list of these 10 public holidays:

1. Confraternização Universal : четверг, 1 январь, 1987
2. Terça-feira de Carnaval : вторник, 3 март, 1987
3. Sexta Feira Santa ou Paixão de Cristo : пятница, 17 апрель, 1987
4. Tiradentes : вторник, 21 апрель, 1987
5. Dia do Trabalho : пятница, 1 май, 1987
6. Corpus Christi : четверг, 18 июнь, 1987
7. Independência do Brasil : понедельник, 7 сентябрь, 1987
8. Nossa Senhora Aparecida : понедельник, 12 октябрь, 1987
9. Finados : понедельник, 2 ноябрь, 1987
10. Natal : пятница, 25 декабрь, 1987

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

1. Criação do estado Mato Grosso do Sul : воскресенье, 11 октябрь, 1987
2. Proclamação da República Brasileira : воскресенье, 15 ноябрь, 1987