Define a period

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How many working days in year 1973?

Here is the detail of the calculation:

Because 1973 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 9 public holidays that do not fall during a weekend and we obtain 252 working days in 1973.

Here is the list of these 9 public holidays:

1. New Year's Day : Monday, 1 January, 1973
2. Easter Monday : Monday, 23 April, 1973
3. Labor Day : Tuesday, 1 May, 1973
4. Iris Day : Tuesday, 8 May, 1973
5. Ascension Day : Thursday, 31 May, 1973
6. Pentecost Monday : Monday, 11 June, 1973
7. Assumption of Mary : Wednesday, 15 August, 1973
8. All Saints' Day : Thursday, 1 November, 1973
9. Christmas Day : Tuesday, 25 December, 1973

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

1. National Day : Saturday, 21 July, 1973
2. Armistice Day : Sunday, 11 November, 1973