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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. Karfreitag : пятница, 25 март, 1921
2. Ostermontag : понедельник, 28 март, 1921
3. Pfingstmontag : понедельник, 16 май, 1921
4. Tag der Deutschen Einheit : понедельник, 3 октябрь, 1921
5. Zweiter Weihnachtsfeiertag : понедельник, 26 декабрь, 1921

And here are the 5 public holidays falling on a weekend:

1. Neujahrstag : суббота, 1 январь, 1921
2. Tag der Arbeit : воскресенье, 1 май, 1921
3. Heiligabend : суббота, 24 декабрь, 1921
4. Weihnachtstag : воскресенье, 25 декабрь, 1921
5. Silvester : суббота, 31 декабрь, 1921