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How many working days in year 1973?

Here is the detail of the calculation:

Because 1973 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 12 public holidays that do not fall during a weekend and we obtain 249 working days in 1973.

Here is the list of these 12 public holidays:

1. Confraternização Universal : понедельник, 1 январь, 1973
2. Aniversário de São Paulo : четверг, 25 январь, 1973
3. Terça-feira de Carnaval : вторник, 6 март, 1973
4. Sexta Feira Santa ou Paixão de Cristo : пятница, 20 апрель, 1973
5. Dia do Trabalho : вторник, 1 май, 1973
6. Corpus Christi : четверг, 21 июнь, 1973
7. Revolução constitucionalista : понедельник, 9 июль, 1973
8. Independência do Brasil : пятница, 7 сентябрь, 1973
9. Nossa Senhora Aparecida : пятница, 12 октябрь, 1973
10. Finados : пятница, 2 ноябрь, 1973
11. Proclamação da República Brasileira : четверг, 15 ноябрь, 1973
12. Natal : вторник, 25 декабрь, 1973

And here is the public holiday falling on a weekend:

1. Tiradentes : суббота, 21 апрель, 1973