Define a period

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How many working days in year 1991?

Here is the detail of the calculation:

Because 1991 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 12 public holidays that do not fall during a weekend and we obtain 249 working days in 1991.

Here is the list of these 12 public holidays:

1. New Year's Day : Tuesday, 1 January, 1991
2. National day (observance) : Monday, 4 March, 1991
3. Orthodox Easter Friday : Friday, 5 April, 1991
4. Orthodox Easter Monday : Monday, 8 April, 1991
5. Labour Day : Wednesday, 1 May, 1991
6. St. George's Day : Monday, 6 May, 1991
7. Culture and Literacy Day : Friday, 24 May, 1991
8. Unification Day : Friday, 6 September, 1991
9. Independence Day (observance) : Monday, 23 September, 1991
10. Christmas Eve : Tuesday, 24 December, 1991
11. Christmas Day : Wednesday, 25 December, 1991
12. Boxing day : Thursday, 26 December, 1991

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

1. National day : Sunday, 3 March, 1991
2. Orthodox Easter Saturday : Saturday, 6 April, 1991
3. Orthodox Easter Sunday : Sunday, 7 April, 1991
4. Independence Day : Sunday, 22 September, 1991