Define a period

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How many working days in year 1974?

Here is the detail of the calculation:

Because 1974 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 10 public holidays that do not fall during a weekend and we obtain 251 working days in 1974.

Here is the list of these 10 public holidays:

1. New Year's Day : Tuesday, 1 January, 1974
2. Easter Monday : Monday, 15 April, 1974
3. Labor Day : Wednesday, 1 May, 1974
4. Ascension Day : Thursday, 23 May, 1974
5. Pentecost Monday : Monday, 3 June, 1974
6. Assumption of Mary : Thursday, 15 August, 1974
7. All Saints' Day : Friday, 1 November, 1974
8. Armistice Day : Monday, 11 November, 1974
9. King's Day : Friday, 15 November, 1974
10. Christmas Day : Wednesday, 25 December, 1974

And here is the public holiday falling on a weekend:

1. National Day : Sunday, 21 July, 1974