Define a period

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How many working days in year 1977?

Here is the detail of the calculation:

Because 1977 is not a leap year, it has 365 days.

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

Now, let's remove 7 public holidays that do not fall during a weekend and we obtain 253 working days in 1977.

Here is the list of these 7 public holidays:

1. Skjærtorsdag : Thursday, 7 April, 1977
2. Langfredag : Friday, 8 April, 1977
3. Andre påskedag : Monday, 11 April, 1977
4. Grunnlovsdagen : Tuesday, 17 May, 1977
5. Kristi Himmelfartsdag : Thursday, 19 May, 1977
6. Andre pinsedag : Monday, 30 May, 1977
7. Andre Juledag : Monday, 26 December, 1977

And here are the 5 public holidays falling on a weekend:

1. Første nyttårsdag : Saturday, 1 January, 1977
2. Første påskedag : Sunday, 10 April, 1977
3. Første mai : Sunday, 1 May, 1977
4. Første pinsedag : Sunday, 29 May, 1977
5. Første Juledag : Sunday, 25 December, 1977