Define a period

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How many working days in year 1972?

Here is the detail of the calculation:

Because 1972 is a leap year, it has 366 days.

Let's remove 53 saturdays and 53 sundays. It remains 260 days.

Now, let's remove 8 public holidays that do not fall during a weekend and we obtain 252 working days in 1972.

Here is the list of these 8 public holidays:

1. Easter Monday : Monday, 3 April, 1972
2. Labor Day : Monday, 1 May, 1972
3. Ascension Day : Thursday, 11 May, 1972
4. Pentecost Monday : Monday, 22 May, 1972
5. National Day : Friday, 21 July, 1972
6. Assumption of Mary : Tuesday, 15 August, 1972
7. All Saints' Day : Wednesday, 1 November, 1972
8. Christmas Day : Monday, 25 December, 1972

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

1. New Year's Day : Saturday, 1 January, 1972
2. Armistice Day : Saturday, 11 November, 1972