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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 9 public holidays that do not fall during a weekend and we obtain 253 working days in 1980.

Here is the list of these 9 public holidays:

1. New Year's Day : вторник, 1 январь, 1980
2. Makar Sankranti : понедельник, 14 январь, 1980
3. Maharaja Shivaji Jayanti : вторник, 19 февраль, 1980
4. Good Friday : пятница, 4 апрель, 1980
5. Mesadi : понедельник, 14 апрель, 1980
6. Independence Day : пятница, 15 август, 1980
7. Mahatma Gandhi's Birthday : четверг, 2 октябрь, 1980
8. Christmas Eve : среда, 24 декабрь, 1980
9. Christmas : четверг, 25 декабрь, 1980

And here is the public holiday falling on a weekend:

1. Republic Day : суббота, 26 январь, 1980