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How many working days in year 1931?

Here is the detail of the calculation:

Because 1931 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 12 public holidays that do not fall during a weekend and we obtain 249 working days in 1931.

Here is the list of these 12 public holidays:

1. New Year's Day : четверг, январь 1, 1931
2. Martin Luther King Day : понедельник, январь 19, 1931
3. Washington's Birthday : понедельник, февраль 16, 1931
4. Good Friday : пятница, апрель 3, 1931
5. Memorial Day : понедельник, май 25, 1931
6. Juneteenth National Independence Day : пятница, июнь 19, 1931
7. Independence Day (observance) : пятница, июль 3, 1931
8. Labor Day : понедельник, сентябрь 7, 1931
9. Veterans Day : среда, ноябрь 11, 1931
10. Thanksgiving : четверг, ноябрь 26, 1931
11. Christmas Eve : четверг, декабрь 24, 1931
12. Christmas : пятница, декабрь 25, 1931

And here is the public holiday falling on a weekend:

1. Independence Day : суббота, июль 4, 1931