Define a period

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How many working days in year 1972?

Here is the detail of the calculation:

Because 1972 is a leap year, it has 366 days.

Let's remove 53 saturdays and 53 sundays. It remains 260 days.

Now, let's remove 11 public holidays that do not fall during a weekend and we obtain 249 working days in 1972.

Here is the list of these 11 public holidays:

1. Viernes Santo : Friday, 31 March, 1972
2. Día Internacional de los Trabajadores : Monday, 1 May, 1972
3. San Pedro y San Pablo : Monday, 26 June, 1972
4. Asunción de la Virgen : Tuesday, 15 August, 1972
5. Fiestas Patrias : Monday, 18 September, 1972
6. Día de las Glorias del Ejércitos : Tuesday, 19 September, 1972
7. Día del Descubrimiento de Dos Mundos : Monday, 9 October, 1972
8. Día Nacional de las Iglesias Evangélicas y Protestantes : Friday, 27 October, 1972
9. Día de Todos los Santos : Wednesday, 1 November, 1972
10. Día de la Inmaculada Concepción : Friday, 8 December, 1972
11. Navidad : Monday, 25 December, 1972

And here are the 4 public holidays falling on a weekend:

1. Año Nuevo : Saturday, 1 January, 1972
2. Sábado Santo : Saturday, 1 April, 1972
3. Día de las Glorias Navales : Sunday, 21 May, 1972
4. Virgen del Carmen : Sunday, 16 July, 1972