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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. New Year's Day : понедельник, январь 1, 1990
2. Martin Luther King Day : понедельник, январь 15, 1990
3. Washington's Birthday : понедельник, февраль 19, 1990
4. Memorial Day : понедельник, май 28, 1990
5. Juneteenth National Independence Day : вторник, июнь 19, 1990
6. Independence Day : среда, июль 4, 1990
7. Labor Day : понедельник, сентябрь 3, 1990
8. Veterans Day (observance) : понедельник, ноябрь 12, 1990
9. Thanksgiving : четверг, ноябрь 22, 1990
10. Black Friday : пятница, ноябрь 23, 1990
11. Christmas : вторник, декабрь 25, 1990

And here is the public holiday falling on a weekend:

1. Veterans Day : воскресенье, ноябрь 11, 1990