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How many working days in year 1917?

Here is the detail of the calculation:

Because 1917 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 11 public holidays that do not fall during a weekend and we obtain 250 working days in 1917.

Here is the list of these 11 public holidays:

1. New Year's Day : понедельник, 1 январь, 1917
2. National Day : четверг, 15 март, 1917
3. Good Friday : пятница, 6 апрель, 1917
4. Easter Monday : понедельник, 9 апрель, 1917
5. Labour Day : вторник, 1 май, 1917
6. Pentecost Monday : понедельник, 28 май, 1917
7. State Foundation Day : понедельник, 20 август, 1917
8. National Day : вторник, 23 октябрь, 1917
9. All Saints' Day : четверг, 1 ноябрь, 1917
10. Christmas Day : вторник, 25 декабрь, 1917
11. Second Day of Christmas : среда, 26 декабрь, 1917

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

1. Easter Sunday : воскресенье, 8 апрель, 1917
2. Pentecost Sunday : воскресенье, 27 май, 1917