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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 6 public holidays that do not fall during a weekend and we obtain 255 working days in 1991.

Here is the list of these 6 public holidays:

1. New Year's Day : вторник, 1 январь, 1991
2. National Sovereignty and Children's Day : вторник, 23 апрель, 1991
3. Labour and Solidarity Day : среда, 1 май, 1991
4. Victory Day : пятница, 30 август, 1991
5. Republic Day Eve : понедельник, 28 октябрь, 1991
6. Republic Day : вторник, 29 октябрь, 1991

And here is the public holiday falling on a weekend:

1. Commemoration of Atatürk, Youth and Sports Day : воскресенье, 19 май, 1991