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How many working days in year 1920?

Here is the detail of the calculation:

Because 1920 is a leap year, it has 366 days.

Let's remove 52 saturdays and 52 sundays. It remains 262 days.

Now, let's remove 9 public holidays that do not fall during a weekend and we obtain 253 working days in 1920.

Here is the list of these 9 public holidays:

1. New Year's Day : четверг, 1 январь, 1920
2. Family Day : понедельник, 16 февраль, 1920
3. Good Friday : пятница, 2 апрель, 1920
4. Victoria Day : понедельник, 24 май, 1920
5. Canada Day : четверг, 1 июль, 1920
6. Labour Day : понедельник, 6 сентябрь, 1920
7. Thanksgiving : понедельник, 11 октябрь, 1920
8. Christmas (observance) : понедельник, 27 декабрь, 1920
9. Boxing Day (observance) : вторник, 28 декабрь, 1920

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

1. Christmas : суббота, 25 декабрь, 1920
2. Boxing Day : воскресенье, 26 декабрь, 1920