Define a period

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How many working days in year 1990?

Here is the detail of the calculation:

Because 1990 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 9 public holidays that do not fall during a weekend and we obtain 252 working days in 1990.

Here is the list of these 9 public holidays:

1. Nytårsdag : Monday, 1 January, 1990
2. Skærtorsdag : Thursday, 12 April, 1990
3. Langfredag : Friday, 13 April, 1990
4. 2. påskedag : Monday, 16 April, 1990
5. Store Bededag : Friday, 11 May, 1990
6. Kristi Himmelfartsdag : Thursday, 24 May, 1990
7. 2. pinsedag : Monday, 4 June, 1990
8. Juledag : Tuesday, 25 December, 1990
9. 2. juledag : Wednesday, 26 December, 1990

And here are the 2 public holidays falling on a weekend:

1. Påskedag : Sunday, 15 April, 1990
2. Pinsedag : Sunday, 3 June, 1990