Define a period

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How many working days in year 1988?

Here is the detail of the calculation:

Because 1988 is a leap year, it has 366 days.

Let's remove 53 saturdays and 52 sundays. It remains 261 days.

Now, let's remove 8 public holidays that do not fall during a weekend and we obtain 253 working days in 1988.

Here is the list of these 8 public holidays:

1. Første nyttårsdag : Friday, 1 January, 1988
2. Skjærtorsdag : Thursday, 31 March, 1988
3. Langfredag : Friday, 1 April, 1988
4. Andre påskedag : Monday, 4 April, 1988
5. Kristi Himmelfartsdag : Thursday, 12 May, 1988
6. Grunnlovsdagen : Tuesday, 17 May, 1988
7. Andre pinsedag : Monday, 23 May, 1988
8. Andre Juledag : Monday, 26 December, 1988

And here are the 4 public holidays falling on a weekend:

1. Første påskedag : Sunday, 3 April, 1988
2. Første mai : Sunday, 1 May, 1988
3. Første pinsedag : Sunday, 22 May, 1988
4. Første Juledag : Sunday, 25 December, 1988