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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 11 public holidays that do not fall during a weekend and we obtain 250 working days in 1991.

Here is the list of these 11 public holidays:

1. New Year's Day : вторник, 1 январь, 1991
2. National Day : пятница, 15 март, 1991
3. Good Friday : пятница, 29 март, 1991
4. Easter Monday : понедельник, 1 апрель, 1991
5. Labour Day : среда, 1 май, 1991
6. Pentecost Monday : понедельник, 20 май, 1991
7. State Foundation Day : вторник, 20 август, 1991
8. National Day : среда, 23 октябрь, 1991
9. All Saints' Day : пятница, 1 ноябрь, 1991
10. Christmas Day : среда, 25 декабрь, 1991
11. Second Day of Christmas : четверг, 26 декабрь, 1991

And here are the 2 public holidays falling on a weekend:

1. Easter Sunday : воскресенье, 31 март, 1991
2. Pentecost Sunday : воскресенье, 19 май, 1991