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 11 public holidays that do not fall during a weekend and we obtain 250 working days in 1991.

Here is the list of these 11 public holidays:

1. Πρωτοχρονιά : Tuesday, 1 January, 1991
2. Καθαρά Δευτέρα : Monday, 18 February, 1991
3. Εικοστή Πέμπτη Μαρτίου : Monday, 25 March, 1991
4. Μεγάλη Παρασκευή : Friday, 5 April, 1991
5. Δευτέρα του Πάσχα : Monday, 8 April, 1991
6. Εργατική Πρωτομαγιά : Wednesday, 1 May, 1991
7. Δευτέρα Πεντηκοστής : Monday, 27 May, 1991
8. Κοίμηση της Θεοτόκου : Thursday, 15 August, 1991
9. Ημέρα του Όχι : Monday, 28 October, 1991
10. Χριστούγεννα : Wednesday, 25 December, 1991
11. Σύναξη της Θεοτόκου : Thursday, 26 December, 1991

And here are the 3 public holidays falling on a weekend:

1. Θεοφάνεια : Sunday, 6 January, 1991
2. Ορθόδοξο Πάσχα : Sunday, 7 April, 1991
3. Πεντηκοστή : Sunday, 26 May, 1991