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 7 public holidays that do not fall during a weekend and we obtain 255 working days in 1976.

Here is the list of these 7 public holidays:

1. Año Nuevo : Thursday, 1 January, 1976
2. Día de la Constitución : Monday, 2 February, 1976
3. Natalicio de Benito Juárez : Monday, 15 March, 1976
4. Viernes Santo : Friday, 16 April, 1976
5. Día de la Independencia : Thursday, 16 September, 1976
6. Día de la Revolución : Monday, 15 November, 1976
7. Transmisión del Poder Ejecutivo Federal : Wednesday, 1 December, 1976

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

1. Día del Trabajo : Saturday, 1 May, 1976
2. Navidad : Saturday, 25 December, 1976