Define a period

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How many working days in year 2018?

Here is the detail of the calculation:

Because 2018 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 12 public holidays that do not fall during a weekend and we obtain 249 working days in 2018.

Here is the list of these 12 public holidays:

1. Año Nuevo : Monday, 1 January, 2018
2. Jueves Santo : Thursday, 29 March, 2018
3. Viernes Santo : Friday, 30 March, 2018
4. Día del Trabajo : Tuesday, 1 May, 2018
5. Batalla de Arica y Día de la Bandera : Thursday, 7 June, 2018
6. Día de San Pedro y San Pablo : Friday, 29 June, 2018
7. Día de la Fuerza Aérea : Monday, 23 July, 2018
8. Batalla de Junin : Monday, 6 August, 2018
9. Día de Santa Rosa de Lima : Thursday, 30 August, 2018
10. Combate de Angamos : Monday, 8 October, 2018
11. Día de Todos los Santos : Thursday, 1 November, 2018
12. Navidad : Tuesday, 25 December, 2018

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

1. Día de la Independencia : Saturday, 28 July, 2018
2. Día de la Independencia : Sunday, 29 July, 2018
3. Día de la Inmaculada Concepción : Saturday, 8 December, 2018
4. Batalla de Ayacucho : Sunday, 9 December, 2018