Define a period

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How many working days in year 1977?

Here is the detail of the calculation:

Because 1977 is not a leap year, it has 365 days.

Let's remove 53 saturdays and 52 sundays. It remains 260 days.

Now, let's remove 8 public holidays that do not fall during a weekend and we obtain 252 working days in 1977.

Here is the list of these 8 public holidays:

1. Prešernov dan : Tuesday, 8 February, 1977
2. Velikonočni ponedeljek : Monday, 11 April, 1977
3. Dan upora proti okupatorju : Wednesday, 27 April, 1977
4. Praznik dela : Monday, 2 May, 1977
5. Marijino vnebovzetje : Monday, 15 August, 1977
6. Dan reformacije : Monday, 31 October, 1977
7. Dan spomina na mrtve : Tuesday, 1 November, 1977
8. Dan samostojnosti in enotnosti : Monday, 26 December, 1977

And here are the 7 public holidays falling on a weekend:

1. Novo leto : Saturday, 1 January, 1977
2. Novoletni dan : Sunday, 2 January, 1977
3. Velika noč : Sunday, 10 April, 1977
4. Praznik dela : Sunday, 1 May, 1977
5. Binkošti : Sunday, 29 May, 1977
6. Dan državnosti : Saturday, 25 June, 1977
7. Božič : Sunday, 25 December, 1977