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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 7 public holidays that do not fall during a weekend and we obtain 253 working days in 1921.

Here is the list of these 7 public holidays:

1. Maundy Thursday : четверг, 24 март, 1921
2. Good Friday : пятница, 25 март, 1921
3. Easter Monday : понедельник, 28 март, 1921
4. General Prayer Day : пятница, 22 апрель, 1921
5. Ascension Day : четверг, 5 май, 1921
6. Whit Monday : понедельник, 16 май, 1921
7. Boxing Day : понедельник, 26 декабрь, 1921

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

1. New Year's Day : суббота, 1 январь, 1921
2. Easter Sunday : воскресенье, 27 март, 1921
3. Pentecost : воскресенье, 15 май, 1921
4. Christmas Day : воскресенье, 25 декабрь, 1921