Define a period

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How many working days in year 1990?

Here is the detail of the calculation:

Because 1990 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 1990.

Here is the list of these 10 public holidays:

1. Nova godina : Monday, 1 January, 1990
2. Uskrsni ponedjeljak : Monday, 16 April, 1990
3. Praznik rada : Tuesday, 1 May, 1990
4. Dan državnosti : Wednesday, 30 May, 1990
5. Tijelovo : Thursday, 14 June, 1990
6. Dan antifašističke borbe : Friday, 22 June, 1990
7. Velika Gospa : Wednesday, 15 August, 1990
8. Svi sveti : Thursday, 1 November, 1990
9. Božić : Tuesday, 25 December, 1990
10. Sveti Stjepan : Wednesday, 26 December, 1990

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

1. Bogojavljenje : Saturday, 6 January, 1990
2. Uskrs : Sunday, 15 April, 1990
3. Dan pobjede i domovinske zahvalnosti : Sunday, 5 August, 1990
4. Dan sjećanja : Sunday, 18 November, 1990