Define a period

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How many working days in year 1991?

Here is the detail of the calculation:

Because 1991 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 1991.

Here is the list of these 10 public holidays:

1. Nova godina : Tuesday, 1 January, 1991
2. Uskrsni ponedjeljak : Monday, 1 April, 1991
3. Praznik rada : Wednesday, 1 May, 1991
4. Dan državnosti : Thursday, 30 May, 1991
5. Dan pobjede i domovinske zahvalnosti : Monday, 5 August, 1991
6. Velika Gospa : Thursday, 15 August, 1991
7. Svi sveti : Friday, 1 November, 1991
8. Dan sjećanja : Monday, 18 November, 1991
9. Božić : Wednesday, 25 December, 1991
10. Sveti Stjepan : Thursday, 26 December, 1991

And here are the 3 public holidays falling on a weekend:

1. Bogojavljenje : Sunday, 6 January, 1991
2. Uskrs : Sunday, 31 March, 1991
3. Dan antifašističke borbe : Saturday, 22 June, 1991