Define a period

...

How many working days in year 2057?

Here is the detail of the calculation:

Because 2057 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 2057.

Here is the list of these 12 public holidays:

1. Año Nuevo : Monday, 1 January, 2057
2. Jueves Santo : Thursday, 19 April, 2057
3. Viernes Santo : Friday, 20 April, 2057
4. Día del Trabajo : Tuesday, 1 May, 2057
5. Batalla de Arica y Día de la Bandera : Thursday, 7 June, 2057
6. Día de San Pedro y San Pablo : Friday, 29 June, 2057
7. Día de la Fuerza Aérea : Monday, 23 July, 2057
8. Batalla de Junin : Monday, 6 August, 2057
9. Día de Santa Rosa de Lima : Thursday, 30 August, 2057
10. Combate de Angamos : Monday, 8 October, 2057
11. Día de Todos los Santos : Thursday, 1 November, 2057
12. Navidad : Tuesday, 25 December, 2057

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

1. Día de la Independencia : Saturday, 28 July, 2057
2. Día de la Independencia : Sunday, 29 July, 2057
3. Día de la Inmaculada Concepción : Saturday, 8 December, 2057
4. Batalla de Ayacucho : Sunday, 9 December, 2057