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How many working days in year 1991?

Here is the detail of the calculation:

Because 1991 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 1991.

Here is the list of these 10 public holidays:

1. Solenidade da Santa Mãe de Deus : вторник, 1 январь, 1991
2. Sexta-Feira Santa : пятница, 29 март, 1991
3. Dia da Liberdade : четверг, 25 апрель, 1991
4. Dia do Trabalhador : среда, 1 май, 1991
5. Dia dos Açores : понедельник, 20 май, 1991
6. Corpo de Deus : четверг, 30 май, 1991
7. Dia de Portugal : понедельник, 10 июнь, 1991
8. Assunção de Nossa Senhora : четверг, 15 август, 1991
9. Todos os Santos : пятница, 1 ноябрь, 1991
10. Natal : среда, 25 декабрь, 1991

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

1. Páscoa : воскресенье, 31 март, 1991
2. Implantação da República : суббота, 5 октябрь, 1991
3. Restauração da Independência : воскресенье, 1 декабрь, 1991
4. Dia da Imaculada Conceição : воскресенье, 8 декабрь, 1991