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How many working days in year 1981?

Here is the detail of the calculation:

Because 1981 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 14 public holidays that do not fall during a weekend and we obtain 247 working days in 1981.

Here is the list of these 14 public holidays:

1. New Year's Day : четверг, январь 1, 1981
2. Martin Luther King Day : понедельник, январь 19, 1981
3. Good Friday : пятница, апрель 17, 1981
4. Memorial Day : понедельник, май 25, 1981
5. Juneteenth National Independence Day : пятница, июнь 19, 1981
6. Independence Day (observance) : пятница, июль 3, 1981
7. Labor Day : понедельник, сентябрь 7, 1981
8. Election Day : вторник, ноябрь 3, 1981
9. Veterans Day : среда, ноябрь 11, 1981
10. Thanksgiving : четверг, ноябрь 26, 1981
11. Black Friday : пятница, ноябрь 27, 1981
12. Christmas Eve : четверг, декабрь 24, 1981
13. Christmas : пятница, декабрь 25, 1981
14. New Year's Eve : четверг, декабрь 31, 1981

And here is the public holiday falling on a weekend:

1. Independence Day : суббота, июль 4, 1981