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How many working days in year 1981?

Here is the detail of the calculation:

Because 1981 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 8 public holidays that do not fall during a weekend and we obtain 253 working days in 1981.

Here is the list of these 8 public holidays:

1. New Year's Day : четверг, 1 январь, 1981
2. Maundy Thursday : четверг, 16 апрель, 1981
3. Good Friday : пятница, 17 апрель, 1981
4. Easter Monday : понедельник, 20 апрель, 1981
5. Labour Day : пятница, 1 май, 1981
6. Ascension Day : четверг, 28 май, 1981
7. Whit Monday : понедельник, 8 июнь, 1981
8. Christmas Day : пятница, 25 декабрь, 1981

And here are the 4 public holidays falling on a weekend:

1. Easter Sunday : воскресенье, 19 апрель, 1981
2. Constitution Day : воскресенье, 17 май, 1981
3. Pentecost : воскресенье, 7 июнь, 1981
4. St Stephen's Day : суббота, 26 декабрь, 1981