Define a period

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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 12 public holidays that do not fall during a weekend and we obtain 250 working days in 1980.

Here is the list of these 12 public holidays:

1. New Year's Day : Tuesday, 1 January, 1980
2. National day : Monday, 3 March, 1980
3. Orthodox Easter Friday : Friday, 4 April, 1980
4. Orthodox Easter Monday : Monday, 7 April, 1980
5. Labour Day : Thursday, 1 May, 1980
6. St. George's Day : Tuesday, 6 May, 1980
7. Culture and Literacy Day (observance) : Monday, 26 May, 1980
8. Unification Day (observance) : Monday, 8 September, 1980
9. Independence Day : Monday, 22 September, 1980
10. Christmas Eve : Wednesday, 24 December, 1980
11. Christmas Day : Thursday, 25 December, 1980
12. Boxing day : Friday, 26 December, 1980

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

1. Orthodox Easter Saturday : Saturday, 5 April, 1980
2. Orthodox Easter Sunday : Sunday, 6 April, 1980
3. Culture and Literacy Day : Saturday, 24 May, 1980
4. Unification Day : Saturday, 6 September, 1980