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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 5 public holidays that do not fall during a weekend and we obtain 256 working days in 1990.

Here is the list of these 5 public holidays:

1. New Year's Day : понедельник, 1 январь, 1990
2. Good Friday : пятница, 13 апрель, 1990
3. Labour Day : вторник, 1 май, 1990
4. National Day : четверг, 9 август, 1990
5. Christmas Day : вторник, 25 декабрь, 1990