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How many working days in year 1980?

Here is the detail of the calculation:

Because 1980 is a leap year, it has 366 days.

Let's remove 52 saturdays and 52 sundays. It remains 262 days.

Now, let's remove 9 public holidays that do not fall during a weekend and we obtain 253 working days in 1980.

Here is the list of these 9 public holidays:

1. New Year's Day : вторник, 1 январь, 1980
2. Good Friday : пятница, 4 апрель, 1980
3. Spring Day : четверг, 1 май, 1980
4. Victory Day : понедельник, 23 июнь, 1980
5. Midsummer Day : вторник, 24 июнь, 1980
6. Independence Restoration Day : среда, 20 август, 1980
7. Christmas Eve : среда, 24 декабрь, 1980
8. Christmas Day : четверг, 25 декабрь, 1980
9. Second Day of Christmas : пятница, 26 декабрь, 1980

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

1. Independence Day : воскресенье, 24 февраль, 1980
2. Easter : воскресенье, 6 апрель, 1980
3. Pentecost : воскресенье, 25 май, 1980