Define a period

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How many working days in year 1920?

Here is the detail of the calculation:

Because 1920 is a leap year, it has 366 days.

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

Now, let's remove 7 public holidays that do not fall during a weekend and we obtain 255 working days in 1920.

Here is the list of these 7 public holidays:

1. Uusaasta : Thursday, 1 January, 1920
2. Iseseisvuspäev : Tuesday, 24 February, 1920
3. Suur Reede : Friday, 2 April, 1920
4. Võidupüha : Wednesday, 23 June, 1920
5. Jaanipäev : Thursday, 24 June, 1920
6. Taasiseseisvumispäev : Friday, 20 August, 1920
7. Jõululaupäev : Friday, 24 December, 1920

And here are the 5 public holidays falling on a weekend:

1. Ülestõusmispühad : Sunday, 4 April, 1920
2. Kevadpüha : Saturday, 1 May, 1920
3. Nelipühad : Sunday, 23 May, 1920
4. Esimene jõulupüha : Saturday, 25 December, 1920
5. Teine jõulupüha : Sunday, 26 December, 1920