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How many working days in year 1921?

Here is the detail of the calculation:

Because 1921 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 1921.

Here is the list of these 9 public holidays:

1. Sexta-Feira Santa : пятница, 25 март, 1921
2. Dia da Liberdade : понедельник, 25 апрель, 1921
3. Corpo de Deus : четверг, 26 май, 1921
4. Dia de Portugal : пятница, 10 июнь, 1921
5. Assunção de Nossa Senhora : понедельник, 15 август, 1921
6. Implantação da República : среда, 5 октябрь, 1921
7. Todos os Santos : вторник, 1 ноябрь, 1921
8. Restauração da Independência : четверг, 1 декабрь, 1921
9. Dia da Imaculada Conceição : четверг, 8 декабрь, 1921

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

1. Solenidade da Santa Mãe de Deus : суббота, 1 январь, 1921
2. Páscoa : воскресенье, 27 март, 1921
3. Dia do Trabalhador : воскресенье, 1 май, 1921
4. Natal : воскресенье, 25 декабрь, 1921