Define a period

...

How many working days in year 1965?

Here is the detail of the calculation:

Because 1965 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 1965.

Here is the list of these 6 public holidays:

1. Neijoerschdag : Friday, 1 January, 1965
2. Ouschterméindeg : Monday, 19 April, 1965
3. Christi Himmelfaart : Thursday, 27 May, 1965
4. Péngschtméindeg : Monday, 7 June, 1965
5. Nationalfeierdag : Wednesday, 23 June, 1965
6. Allerhellegen : Monday, 1 November, 1965

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

1. Dag vun der Aarbecht : Saturday, 1 May, 1965
2. Léiffrawëschdag : Sunday, 15 August, 1965
3. Chrëschtdag : Saturday, 25 December, 1965
4. Stiefesdag : Sunday, 26 December, 1965