Define a period

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How many working days in year 1983?

Here is the detail of the calculation:

Because 1983 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 1983.

Here is the list of these 9 public holidays:

1. Sexta-Feira Santa : Friday, 1 April, 1983
2. Dia da Liberdade : Monday, 25 April, 1983
3. Corpo de Deus : Thursday, 2 June, 1983
4. Dia de Portugal : Friday, 10 June, 1983
5. Assunção de Nossa Senhora : Monday, 15 August, 1983
6. Implantação da República : Wednesday, 5 October, 1983
7. Todos os Santos : Tuesday, 1 November, 1983
8. Restauração da Independência : Thursday, 1 December, 1983
9. Dia da Imaculada Conceição : Thursday, 8 December, 1983

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

1. Solenidade da Santa Mãe de Deus : Saturday, 1 January, 1983
2. Páscoa : Sunday, 3 April, 1983
3. Dia do Trabalhador : Sunday, 1 May, 1983
4. Natal : Sunday, 25 December, 1983