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How many working days in year 1921?

Here is the detail of the calculation:

Because 1921 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 5 public holidays that do not fall during a weekend and we obtain 255 working days in 1921.

Here is the list of these 5 public holidays:

1. Independence Day : четверг, 24 февраль, 1921
2. Good Friday : пятница, 25 март, 1921
3. Victory Day : четверг, 23 июнь, 1921
4. Midsummer Day : пятница, 24 июнь, 1921
5. Second Day of Christmas : понедельник, 26 декабрь, 1921

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

1. New Year's Day : суббота, 1 январь, 1921
2. Easter : воскресенье, 27 март, 1921
3. Spring Day : воскресенье, 1 май, 1921
4. Pentecost : воскресенье, 15 май, 1921
5. Independence Restoration Day : суббота, 20 август, 1921
6. Christmas Eve : суббота, 24 декабрь, 1921
7. Christmas Day : воскресенье, 25 декабрь, 1921