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 7 public holidays that do not fall during a weekend and we obtain 253 working days in 1983.

Here is the list of these 7 public holidays:

1. Lunes de Carnaval : Monday, 14 February, 1983
2. Martes de Carnaval : Tuesday, 15 February, 1983
3. Viernes Santo : Friday, 1 April, 1983
4. Día del Trabajo : Monday, 2 May, 1983
5. Batalla de Pichincha : Monday, 23 May, 1983
6. Independencia de Guayaquil : Monday, 10 October, 1983
7. Día de los Difuntos : Friday, 4 November, 1983

And here are the 2 public holidays falling on a weekend:

1. Año Nuevo : Saturday, 1 January, 1983
2. Navidad : Sunday, 25 December, 1983