Define a period

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How many working days in year 1970?

Here is the detail of the calculation:

Because 1970 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 7 public holidays that do not fall during a weekend and we obtain 254 working days in 1970.

Here is the list of these 7 public holidays:

1. Neijoerschdag : Thursday, 1 January, 1970
2. Ouschterméindeg : Monday, 30 March, 1970
3. Dag vun der Aarbecht : Friday, 1 May, 1970
4. Christi Himmelfaart : Thursday, 7 May, 1970
5. Péngschtméindeg : Monday, 18 May, 1970
6. Nationalfeierdag : Tuesday, 23 June, 1970
7. Chrëschtdag : Friday, 25 December, 1970

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

1. Léiffrawëschdag : Saturday, 15 August, 1970
2. Allerhellegen : Sunday, 1 November, 1970
3. Stiefesdag : Saturday, 26 December, 1970