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How many working days in year 1981?

Here is the detail of the calculation:

Because 1981 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 11 public holidays that do not fall during a weekend and we obtain 250 working days in 1981.

Here is the list of these 11 public holidays:

1. Restoration Day of the Independent Czech State : четверг, 1 январь, 1981
2. Good Friday : пятница, 17 апрель, 1981
3. Easter Monday : понедельник, 20 апрель, 1981
4. Labour Day : пятница, 1 май, 1981
5. Liberation Day : пятница, 8 май, 1981
6. Jan Hus Day : понедельник, 6 июль, 1981
7. St Wenceslas Day : понедельник, 28 сентябрь, 1981
8. Independence Day : среда, 28 октябрь, 1981
9. Freedom and Democracy Day : вторник, 17 ноябрь, 1981
10. Christmas Eve : четверг, 24 декабрь, 1981
11. Christmas Day : пятница, 25 декабрь, 1981

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

1. St Cyril and Methodius' Day : воскресенье, 5 июль, 1981
2. St. Stephen's Day : суббота, 26 декабрь, 1981