Define a period

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How many working days in year 1984?

Here is the detail of the calculation:

Because 1984 is a leap year, it has 366 days.

Let's remove 52 saturdays and 53 sundays. It remains 261 days.

Now, let's remove 6 public holidays that do not fall during a weekend and we obtain 255 working days in 1984.

Here is the list of these 6 public holidays:

1. Día de la Constitución : Monday, 6 February, 1984
2. Natalicio de Benito Juárez : Monday, 19 March, 1984
3. Viernes Santo : Friday, 20 April, 1984
4. Día del Trabajo : Tuesday, 1 May, 1984
5. Día de la Revolución : Monday, 19 November, 1984
6. Navidad : Tuesday, 25 December, 1984

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

1. Año Nuevo : Sunday, 1 January, 1984
2. Día de la Independencia : Sunday, 16 September, 1984