Define a period

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How many working days in year 1976?

Here is the detail of the calculation:

Because 1976 is a leap year, it has 366 days.

Let's remove 52 saturdays and 52 sundays. It remains 262 days.

Now, let's remove 9 public holidays that do not fall during a weekend and we obtain 253 working days in 1976.

Here is the list of these 9 public holidays:

1. Año Nuevo : Thursday, 1 January, 1976
2. Jueves Santo : Thursday, 15 April, 1976
3. Viernes Santo : Friday, 16 April, 1976
4. Día del Ejército : Monday, 28 June, 1976
5. Día de la Independencia : Wednesday, 15 September, 1976
6. Día de la Revolución : Wednesday, 20 October, 1976
7. Día de Todos los Santos : Monday, 1 November, 1976
8. Noche Buena : Friday, 24 December, 1976
9. Víspera de Año Nuevo : Friday, 31 December, 1976

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

1. Sábado Santo : Saturday, 17 April, 1976
2. Día del Trabajo : Saturday, 1 May, 1976
3. Navidad : Saturday, 25 December, 1976