Define a period

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How many working days in year 1971?

Here is the detail of the calculation:

Because 1971 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 7 public holidays that do not fall during a weekend and we obtain 254 working days in 1971.

Here is the list of these 7 public holidays:

1. New Year's Day : Friday, 1 January, 1971
2. Easter Monday : Monday, 12 April, 1971
3. Ascension Day : Thursday, 20 May, 1971
4. Pentecost Monday : Monday, 31 May, 1971
5. National Day : Wednesday, 21 July, 1971
6. All Saints' Day : Monday, 1 November, 1971
7. Armistice Day : Thursday, 11 November, 1971

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

1. Labor Day : Saturday, 1 May, 1971
2. Assumption of Mary : Sunday, 15 August, 1971
3. Christmas Day : Saturday, 25 December, 1971