Define a period

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How many working days in year 1967?

Here is the detail of the calculation:

Because 1967 is not a leap year, it has 365 days.

Let's remove 52 saturdays and 53 sundays. It remains 260 days.

Now, let's remove 9 public holidays that do not fall during a weekend and we obtain 251 working days in 1967.

Here is the list of these 9 public holidays:

1. Ouschterméindeg : Monday, 27 March, 1967
2. Dag vun der Aarbecht : Monday, 1 May, 1967
3. Christi Himmelfaart : Thursday, 4 May, 1967
4. Péngschtméindeg : Monday, 15 May, 1967
5. Nationalfeierdag : Friday, 23 June, 1967
6. Léiffrawëschdag : Tuesday, 15 August, 1967
7. Allerhellegen : Wednesday, 1 November, 1967
8. Chrëschtdag : Monday, 25 December, 1967
9. Stiefesdag : Tuesday, 26 December, 1967

And here is the public holiday falling on a weekend:

1. Neijoerschdag : Sunday, 1 January, 1967