Define a period

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How many working days in year 2011?

Here is the detail of the calculation:

Because 2011 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 5 public holidays that do not fall during a weekend and we obtain 255 working days in 2011.

Here is the list of these 5 public holidays:

1. Día de la Constitución : Monday, 7 February, 2011
2. Natalicio de Benito Juárez : Monday, 21 March, 2011
3. Viernes Santo : Friday, 22 April, 2011
4. Día de la Independencia : Friday, 16 September, 2011
5. Día de la Revolución : Monday, 21 November, 2011

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

1. Año Nuevo : Saturday, 1 January, 2011
2. Día del Trabajo : Sunday, 1 May, 2011
3. Navidad : Sunday, 25 December, 2011