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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 12 public holidays that do not fall during a weekend and we obtain 249 working days in 1990.

Here is the list of these 12 public holidays:

1. New Year's Day : понедельник, 1 январь, 1990
2. Second Day of the New Year : вторник, 2 январь, 1990
3. Union of the Romanian Principalities : среда, 24 январь, 1990
4. Orthodox Easter Friday : пятница, 13 апрель, 1990
5. Orthodox Easter Monday : понедельник, 16 апрель, 1990
6. Labour Day : вторник, 1 май, 1990
7. Children's Day : пятница, 1 июнь, 1990
8. Pentecost Monday : понедельник, 4 июнь, 1990
9. Assumption : среда, 15 август, 1990
10. St. Andrew's Day : пятница, 30 ноябрь, 1990
11. Christmas Day : вторник, 25 декабрь, 1990
12. Boxing day : среда, 26 декабрь, 1990

And here are the 3 public holidays falling on a weekend:

1. Orthodox Easter Sunday : воскресенье, 15 апрель, 1990
2. Pentecost Sunday : воскресенье, 3 июнь, 1990
3. National Day : суббота, 1 декабрь, 1990