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How many working days in year 1991?

Here is the detail of the calculation:

Because 1991 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 10 public holidays that do not fall during a weekend and we obtain 251 working days in 1991.

Here is the list of these 10 public holidays:

1. New Year's Day : вторник, 1 январь, 1991
2. Second Day of the New Year : среда, 2 январь, 1991
3. Union of the Romanian Principalities : четверг, 24 январь, 1991
4. Orthodox Easter Friday : пятница, 5 апрель, 1991
5. Orthodox Easter Monday : понедельник, 8 апрель, 1991
6. Labour Day : среда, 1 май, 1991
7. Pentecost Monday : понедельник, 27 май, 1991
8. Assumption : четверг, 15 август, 1991
9. Christmas Day : среда, 25 декабрь, 1991
10. Boxing day : четверг, 26 декабрь, 1991

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

1. Orthodox Easter Sunday : воскресенье, 7 апрель, 1991
2. Pentecost Sunday : воскресенье, 26 май, 1991
3. Children's Day : суббота, 1 июнь, 1991
4. St. Andrew's Day : суббота, 30 ноябрь, 1991
5. National Day : воскресенье, 1 декабрь, 1991