Define a period

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How many working days in year 1999?

Here is the detail of the calculation:

Because 1999 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 7 public holidays that do not fall during a weekend and we obtain 254 working days in 1999.

Here is the list of these 7 public holidays:

1. Første nyttårsdag : Friday, 1 January, 1999
2. Skjærtorsdag : Thursday, 1 April, 1999
3. Langfredag : Friday, 2 April, 1999
4. Andre påskedag : Monday, 5 April, 1999
5. Kristi Himmelfartsdag : Thursday, 13 May, 1999
6. Grunnlovsdagen : Monday, 17 May, 1999
7. Andre pinsedag : Monday, 24 May, 1999

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

1. Første påskedag : Sunday, 4 April, 1999
2. Første mai : Saturday, 1 May, 1999
3. Første pinsedag : Sunday, 23 May, 1999
4. Første Juledag : Saturday, 25 December, 1999
5. Andre Juledag : Sunday, 26 December, 1999