Define a period

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How many working days in year 1979?

Here is the detail of the calculation:

Because 1979 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 10 public holidays that do not fall during a weekend and we obtain 251 working days in 1979.

Here is the list of these 10 public holidays:

1. Første nyttårsdag : Monday, 1 January, 1979
2. Skjærtorsdag : Thursday, 12 April, 1979
3. Langfredag : Friday, 13 April, 1979
4. Andre påskedag : Monday, 16 April, 1979
5. Første mai : Tuesday, 1 May, 1979
6. Grunnlovsdagen : Thursday, 17 May, 1979
7. Kristi Himmelfartsdag : Thursday, 24 May, 1979
8. Andre pinsedag : Monday, 4 June, 1979
9. Første Juledag : Tuesday, 25 December, 1979
10. Andre Juledag : Wednesday, 26 December, 1979

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

1. Første påskedag : Sunday, 15 April, 1979
2. Første pinsedag : Sunday, 3 June, 1979