Define a period

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How many working days in year 1960?

Here is the detail of the calculation:

Because 1960 is a leap year, it has 366 days.

Let's remove 53 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 1960.

Here is the list of these 10 public holidays:

1. Solenidade da Santa Mãe de Deus : Friday, 1 January, 1960
2. Sexta-Feira Santa : Friday, 15 April, 1960
3. Dia da Liberdade : Monday, 25 April, 1960
4. Dia de Portugal : Friday, 10 June, 1960
5. Corpo de Deus : Thursday, 16 June, 1960
6. Assunção de Nossa Senhora : Monday, 15 August, 1960
7. Implantação da República : Wednesday, 5 October, 1960
8. Todos os Santos : Tuesday, 1 November, 1960
9. Restauração da Independência : Thursday, 1 December, 1960
10. Dia da Imaculada Conceição : Thursday, 8 December, 1960

And here are the 3 public holidays falling on a weekend:

1. Páscoa : Sunday, 17 April, 1960
2. Dia do Trabalhador : Sunday, 1 May, 1960
3. Natal : Sunday, 25 December, 1960