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 13 public holidays that do not fall during a weekend and we obtain 248 working days in 1990.

Here is the list of these 13 public holidays:

1. Novo leto : Monday, 1 January, 1990
2. Novoletni dan : Tuesday, 2 January, 1990
3. Prešernov dan : Thursday, 8 February, 1990
4. Velikonočni ponedeljek : Monday, 16 April, 1990
5. Dan upora proti okupatorju : Friday, 27 April, 1990
6. Praznik dela : Tuesday, 1 May, 1990
7. Praznik dela : Wednesday, 2 May, 1990
8. Dan državnosti : Monday, 25 June, 1990
9. Marijino vnebovzetje : Wednesday, 15 August, 1990
10. Dan reformacije : Wednesday, 31 October, 1990
11. Dan spomina na mrtve : Thursday, 1 November, 1990
12. Božič : Tuesday, 25 December, 1990
13. Dan samostojnosti in enotnosti : Wednesday, 26 December, 1990

And here are the 2 public holidays falling on a weekend:

1. Velika noč : Sunday, 15 April, 1990
2. Binkošti : Sunday, 3 June, 1990