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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 10 public holidays that do not fall during a weekend and we obtain 251 working days in 1990.

Here is the list of these 10 public holidays:

1. New Year's Day : понедельник, 1 январь, 1990
2. St. Patrick's Day (substitute day) : понедельник, 19 март, 1990
3. Good Friday : пятница, 13 апрель, 1990
4. Easter Monday : понедельник, 16 апрель, 1990
5. Early May Bank Holiday : понедельник, 7 май, 1990
6. Spring Bank Holiday : понедельник, 28 май, 1990
7. Orangemen's Day : четверг, 12 июль, 1990
8. Late Summer Bank Holiday : понедельник, 27 август, 1990
9. Christmas Day : вторник, 25 декабрь, 1990
10. Boxing Day : среда, 26 декабрь, 1990

And here is the public holiday falling on a weekend:

1. St. Patrick's Day : суббота, 17 март, 1990