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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 9 public holidays that do not fall during a weekend and we obtain 252 working days in 1917.

Here is the list of these 9 public holidays:

1. New Year's Day : понедельник, 1 январь, 1917
2. Easter Monday : понедельник, 9 апрель, 1917
3. Labour Day : вторник, 1 май, 1917
4. Constitution Day : четверг, 3 май, 1917
5. Corpus Christi : четверг, 7 июнь, 1917
6. Assumption of Mary : среда, 15 август, 1917
7. All Saints' Day : четверг, 1 ноябрь, 1917
8. Christmas Day : вторник, 25 декабрь, 1917
9. Boxing Day : среда, 26 декабрь, 1917

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

1. Epiphany : суббота, 6 январь, 1917
2. Easter Sunday : воскресенье, 8 апрель, 1917
3. Pentecost Sunday : воскресенье, 27 май, 1917
4. Independence Day : воскресенье, 11 ноябрь, 1917