Define a period

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How many working days in year 1984?

Here is the detail of the calculation:

Because 1984 is a leap year, it has 366 days.

Let's remove 52 saturdays and 53 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 1984.

Here is the list of these 9 public holidays:

1. Skjærtorsdag : Thursday, 19 April, 1984
2. Langfredag : Friday, 20 April, 1984
3. Andre påskedag : Monday, 23 April, 1984
4. Første mai : Tuesday, 1 May, 1984
5. Grunnlovsdagen : Thursday, 17 May, 1984
6. Kristi Himmelfartsdag : Thursday, 31 May, 1984
7. Andre pinsedag : Monday, 11 June, 1984
8. Første Juledag : Tuesday, 25 December, 1984
9. Andre Juledag : Wednesday, 26 December, 1984

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

1. Første nyttårsdag : Sunday, 1 January, 1984
2. Første påskedag : Sunday, 22 April, 1984
3. Første pinsedag : Sunday, 10 June, 1984