Define a period

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How many working days in year 1989?

Here is the detail of the calculation:

Because 1989 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 1989.

Here is the list of these 9 public holidays:

1. Skjærtorsdag : Thursday, 23 March, 1989
2. Langfredag : Friday, 24 March, 1989
3. Andre påskedag : Monday, 27 March, 1989
4. Første mai : Monday, 1 May, 1989
5. Kristi Himmelfartsdag : Thursday, 4 May, 1989
6. Andre pinsedag : Monday, 15 May, 1989
7. Grunnlovsdagen : Wednesday, 17 May, 1989
8. Første Juledag : Monday, 25 December, 1989
9. Andre Juledag : Tuesday, 26 December, 1989

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

1. Første nyttårsdag : Sunday, 1 January, 1989
2. Første påskedag : Sunday, 26 March, 1989
3. Første pinsedag : Sunday, 14 May, 1989