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How many working days in year 1989?

Here is the detail of the calculation:

Because 1989 is not a leap year, it has 365 days.

Let's remove 52 saturdays and 53 sundays. It remains 260 days.

Now, let's remove 4 public holidays that do not fall during a weekend and we obtain 256 working days in 1989.

Here is the list of these 4 public holidays:

1. Good Friday : пятница, 24 март, 1989
2. Labour Day : понедельник, 1 май, 1989
3. National Day : среда, 9 август, 1989
4. Christmas Day : понедельник, 25 декабрь, 1989

And here is the public holiday falling on a weekend:

1. New Year's Day : воскресенье, 1 январь, 1989