Define a period

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How many working days in year 1940?

Here is the detail of the calculation:

Because 1940 is a leap year, it has 366 days.

Let's remove 52 saturdays and 52 sundays. It remains 262 days.

Now, let's remove 9 public holidays that do not fall during a weekend and we obtain 253 working days in 1940.

Here is the list of these 9 public holidays:

1. New Year's Day : Monday, 1 January, 1940
2. Easter Monday : Monday, 25 March, 1940
3. Labor Day : Wednesday, 1 May, 1940
4. Ascension Day : Thursday, 2 May, 1940
5. Pentecost Monday : Monday, 13 May, 1940
6. Assumption of Mary : Thursday, 15 August, 1940
7. All Saints' Day : Friday, 1 November, 1940
8. Armistice Day : Monday, 11 November, 1940
9. Christmas Day : Wednesday, 25 December, 1940

And here is the public holiday falling on a weekend:

1. National Day : Sunday, 21 July, 1940