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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 7 public holidays that do not fall during a weekend and we obtain 254 working days in 1990.

Here is the list of these 7 public holidays:

1. New Year's Day : понедельник, 1 январь, 1990
2. Good Friday : пятница, 13 апрель, 1990
3. Spring Day : вторник, 1 май, 1990
4. Independence Restoration Day : понедельник, 20 август, 1990
5. Christmas Eve : понедельник, 24 декабрь, 1990
6. Christmas Day : вторник, 25 декабрь, 1990
7. Second Day of Christmas : среда, 26 декабрь, 1990

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

1. Independence Day : суббота, 24 февраль, 1990
2. Easter : воскресенье, 15 апрель, 1990
3. Pentecost : воскресенье, 3 июнь, 1990
4. Victory Day : суббота, 23 июнь, 1990
5. Midsummer Day : воскресенье, 24 июнь, 1990