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How many working days in year 1990?

Here is the detail of the calculation:

Because 1990 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 1990.

Here is the list of these 11 public holidays:

1. Restoration Day of the Independent Czech State : понедельник, 1 январь, 1990
2. Good Friday : пятница, 13 апрель, 1990
3. Easter Monday : понедельник, 16 апрель, 1990
4. Labour Day : вторник, 1 май, 1990
5. Liberation Day : вторник, 8 май, 1990
6. St Cyril and Methodius' Day : четверг, 5 июль, 1990
7. Jan Hus Day : пятница, 6 июль, 1990
8. St Wenceslas Day : пятница, 28 сентябрь, 1990
9. Christmas Eve : понедельник, 24 декабрь, 1990
10. Christmas Day : вторник, 25 декабрь, 1990
11. St. Stephen's Day : среда, 26 декабрь, 1990

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

1. Independence Day : воскресенье, 28 октябрь, 1990
2. Freedom and Democracy Day : суббота, 17 ноябрь, 1990