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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. New Year's Day (observance) : понедельник, 3 январь, 1977
2. Good Friday : пятница, 8 апрель, 1977
3. Victoria Day : понедельник, 23 май, 1977
4. Canada Day : пятница, 1 июль, 1977
5. Labour Day : понедельник, 5 сентябрь, 1977
6. Thanksgiving : понедельник, 10 октябрь, 1977
7. Remembrance Day : пятница, 11 ноябрь, 1977
8. Boxing Day : понедельник, 26 декабрь, 1977
9. Christmas (observance) : вторник, 27 декабрь, 1977

And here are the 2 public holidays falling on a weekend:

1. New Year's Day : суббота, 1 январь, 1977
2. Christmas : воскресенье, 25 декабрь, 1977