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How many working days in year 1980?

Here is the detail of the calculation:

Because 1980 is a leap year, it has 366 days.

Let's remove 52 saturdays and 52 sundays. It remains 262 days.

Now, let's remove 10 public holidays that do not fall during a weekend and we obtain 252 working days in 1980.

Here is the list of these 10 public holidays:

1. New Year's Day : вторник, 1 январь, 1980
2. Australia Day Observance : понедельник, 28 январь, 1980
3. Eight Hours Day : понедельник, 10 март, 1980
4. Good Friday : пятница, 4 апрель, 1980
5. Easter Monday : понедельник, 7 апрель, 1980
6. Easter Tuesday : вторник, 8 апрель, 1980
7. Anzac Day : пятница, 25 апрель, 1980
8. King's Birthday : понедельник, 9 июнь, 1980
9. Christmas Day : четверг, 25 декабрь, 1980
10. Boxing Day : пятница, 26 декабрь, 1980

And here is the public holiday falling on a weekend:

1. Australia Day : суббота, 26 январь, 1980