Define a period

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How many working days in year 1972?

Here is the detail of the calculation:

Because 1972 is a leap year, it has 366 days.

Let's remove 53 saturdays and 53 sundays. It remains 260 days.

Now, let's remove 10 public holidays that do not fall during a weekend and we obtain 250 working days in 1972.

Here is the list of these 10 public holidays:

1. Sexta-Feira Santa : Friday, 31 March, 1972
2. Dia da Liberdade : Tuesday, 25 April, 1972
3. Dia do Trabalhador : Monday, 1 May, 1972
4. Corpo de Deus : Thursday, 1 June, 1972
5. Assunção de Nossa Senhora : Tuesday, 15 August, 1972
6. Implantação da República : Thursday, 5 October, 1972
7. Todos os Santos : Wednesday, 1 November, 1972
8. Restauração da Independência : Friday, 1 December, 1972
9. Dia da Imaculada Conceição : Friday, 8 December, 1972
10. Natal : Monday, 25 December, 1972

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

1. Solenidade da Santa Mãe de Deus : Saturday, 1 January, 1972
2. Páscoa : Sunday, 2 April, 1972
3. Dia de Portugal : Saturday, 10 June, 1972