Define a period

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How many working days in year 1999?

Here is the detail of the calculation:

Because 1999 is not a leap year, it has 365 days.

Let's remove 52 saturdays and 52 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 1999.

Here is the list of these 6 public holidays:

1. Año Nuevo : Friday, 1 January, 1999
2. Día de la Constitución : Monday, 1 February, 1999
3. Natalicio de Benito Juárez : Monday, 15 March, 1999
4. Viernes Santo : Friday, 2 April, 1999
5. Día de la Independencia : Thursday, 16 September, 1999
6. Día de la Revolución : Monday, 15 November, 1999

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

1. Día del Trabajo : Saturday, 1 May, 1999
2. Navidad : Saturday, 25 December, 1999