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How many working days in year 1930?

Here is the detail of the calculation:

Because 1930 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 10 public holidays that do not fall during a weekend and we obtain 251 working days in 1930.

Here is the list of these 10 public holidays:

1. Restoration Day of the Independent Czech State : среда, 1 январь, 1930
2. Good Friday : пятница, 18 апрель, 1930
3. Easter Monday : понедельник, 21 апрель, 1930
4. Labour Day : четверг, 1 май, 1930
5. Liberation Day : четверг, 8 май, 1930
6. Independence Day : вторник, 28 октябрь, 1930
7. Freedom and Democracy Day : понедельник, 17 ноябрь, 1930
8. Christmas Eve : среда, 24 декабрь, 1930
9. Christmas Day : четверг, 25 декабрь, 1930
10. St. Stephen's Day : пятница, 26 декабрь, 1930

And here are the 3 public holidays falling on a weekend:

1. St Cyril and Methodius' Day : суббота, 5 июль, 1930
2. Jan Hus Day : воскресенье, 6 июль, 1930
3. St Wenceslas Day : воскресенье, 28 сентябрь, 1930