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How many working days in year 1990?

Here is the detail of the calculation:

Because 1990 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 6 public holidays that do not fall during a weekend and we obtain 255 working days in 1990.

Here is the list of these 6 public holidays:

1. New Year's Day : понедельник, 1 январь, 1990
2. Islander Day : понедельник, 19 февраль, 1990
3. Good Friday : пятница, 13 апрель, 1990
4. Canada Day (observance) : понедельник, 2 июль, 1990
5. Labour Day : понедельник, 3 сентябрь, 1990
6. Christmas : вторник, 25 декабрь, 1990

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

1. Canada Day : воскресенье, 1 июль, 1990
2. Remembrance Day : воскресенье, 11 ноябрь, 1990