Define a period

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How many working days in year 1987?

Here is the detail of the calculation:

Because 1987 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 10 public holidays that do not fall during a weekend and we obtain 251 working days in 1987.

Here is the list of these 10 public holidays:

1. Año Nuevo : Thursday, 1 January, 1987
2. Viernes Santo : Friday, 17 April, 1987
3. Día Internacional de los Trabajadores : Friday, 1 May, 1987
4. Día de las Glorias Navales : Thursday, 21 May, 1987
5. San Pedro y San Pablo : Monday, 29 June, 1987
6. Virgen del Carmen : Thursday, 16 July, 1987
7. Fiestas Patrias : Friday, 18 September, 1987
8. Día del Descubrimiento de Dos Mundos : Monday, 12 October, 1987
9. Día de la Inmaculada Concepción : Tuesday, 8 December, 1987
10. Navidad : Friday, 25 December, 1987

And here are the 5 public holidays falling on a weekend:

1. Sábado Santo : Saturday, 18 April, 1987
2. Asunción de la Virgen : Saturday, 15 August, 1987
3. Día de las Glorias del Ejércitos : Saturday, 19 September, 1987
4. Día Nacional de las Iglesias Evangélicas y Protestantes : Saturday, 31 October, 1987
5. Día de Todos los Santos : Sunday, 1 November, 1987