Define a period

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How many working days in year 1912?

Here is the detail of the calculation:

Because 1912 is a leap year, it has 366 days.

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

Now, let's remove 8 public holidays that do not fall during a weekend and we obtain 254 working days in 1912.

Here is the list of these 8 public holidays:

1. New Year's Day : Monday, 1 January, 1912
2. Good Friday : Friday, 5 April, 1912
3. Spring Day : Wednesday, 1 May, 1912
4. Midsummer Day : Monday, 24 June, 1912
5. Independence Restoration Day : Tuesday, 20 August, 1912
6. Christmas Eve : Tuesday, 24 December, 1912
7. Christmas Day : Wednesday, 25 December, 1912
8. Second Day of Christmas : Thursday, 26 December, 1912

And here are the 4 public holidays falling on a weekend:

1. Independence Day : Saturday, 24 February, 1912
2. Easter : Sunday, 7 April, 1912
3. Pentecost : Sunday, 26 May, 1912
4. Victory Day : Sunday, 23 June, 1912