Define a period

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How many working days in year 1997?

Here is the detail of the calculation:

Because 1997 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 1997.

Here is the list of these 12 public holidays:

1. Πρωτοχρονιά : Wednesday, 1 January, 1997
2. Θεοφάνεια : Monday, 6 January, 1997
3. Καθαρά Δευτέρα : Monday, 10 March, 1997
4. Εικοστή Πέμπτη Μαρτίου : Tuesday, 25 March, 1997
5. Μεγάλη Παρασκευή : Friday, 25 April, 1997
6. Δευτέρα του Πάσχα : Monday, 28 April, 1997
7. Εργατική Πρωτομαγιά : Thursday, 1 May, 1997
8. Δευτέρα Πεντηκοστής : Monday, 16 June, 1997
9. Κοίμηση της Θεοτόκου : Friday, 15 August, 1997
10. Ημέρα του Όχι : Tuesday, 28 October, 1997
11. Χριστούγεννα : Thursday, 25 December, 1997
12. Σύναξη της Θεοτόκου : Friday, 26 December, 1997

And here are the 2 public holidays falling on a weekend:

1. Ορθόδοξο Πάσχα : Sunday, 27 April, 1997
2. Πεντηκοστή : Sunday, 15 June, 1997