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How many working days in year 1977?

Here is the detail of the calculation:

Because 1977 is not a leap year, it has 365 days.

Let's remove 53 saturdays and 52 sundays. It remains 260 days.

Now, let's remove 5 public holidays that do not fall during a weekend and we obtain 255 working days in 1977.

Here is the list of these 5 public holidays:

1. Independence Day : четверг, 24 февраль, 1977
2. Good Friday : пятница, 8 апрель, 1977
3. Victory Day : четверг, 23 июнь, 1977
4. Midsummer Day : пятница, 24 июнь, 1977
5. Second Day of Christmas : понедельник, 26 декабрь, 1977

And here are the 7 public holidays falling on a weekend:

1. New Year's Day : суббота, 1 январь, 1977
2. Easter : воскресенье, 10 апрель, 1977
3. Spring Day : воскресенье, 1 май, 1977
4. Pentecost : воскресенье, 29 май, 1977
5. Independence Restoration Day : суббота, 20 август, 1977
6. Christmas Eve : суббота, 24 декабрь, 1977
7. Christmas Day : воскресенье, 25 декабрь, 1977