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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 9 public holidays that do not fall during a weekend and we obtain 251 working days in 1977.

Here is the list of these 9 public holidays:

1. Martin Luther King Day : понедельник, январь 17, 1977
2. Good Friday : пятница, апрель 8, 1977
3. Memorial Day : понедельник, май 30, 1977
4. Juneteenth (observance) : понедельник, июнь 20, 1977
5. Independence Day : понедельник, июль 4, 1977
6. Labor Day : понедельник, сентябрь 5, 1977
7. Veterans Day : пятница, ноябрь 11, 1977
8. Thanksgiving : четверг, ноябрь 24, 1977
9. Christmas (observance) : понедельник, декабрь 26, 1977

And here are the 4 public holidays falling on a weekend:

1. New Year's Day : суббота, январь 1, 1977
2. Juneteenth National Independence Day : воскресенье, июнь 19, 1977
3. Christmas Eve : суббота, декабрь 24, 1977
4. Christmas : воскресенье, декабрь 25, 1977