Define a period

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How many working days in year 1904?

Here is the detail of the calculation:

Because 1904 is a leap year, it has 366 days.

Let's remove 53 saturdays and 52 sundays. It remains 261 days.

Now, let's remove 6 public holidays that do not fall during a weekend and we obtain 255 working days in 1904.

Here is the list of these 6 public holidays:

1. New Year's Day : Friday, 1 January, 1904
2. Independence Day : Wednesday, 24 February, 1904
3. Good Friday : Friday, 1 April, 1904
4. Victory Day : Thursday, 23 June, 1904
5. Midsummer Day : Friday, 24 June, 1904
6. Second Day of Christmas : Monday, 26 December, 1904

And here are the 6 public holidays falling on a weekend:

1. Easter : Sunday, 3 April, 1904
2. Spring Day : Sunday, 1 May, 1904
3. Pentecost : Sunday, 22 May, 1904
4. Independence Restoration Day : Saturday, 20 August, 1904
5. Christmas Eve : Saturday, 24 December, 1904
6. Christmas Day : Sunday, 25 December, 1904