Define a period

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How many working days in year 1921?

Here is the detail of the calculation:

Because 1921 is not a leap year, it has 365 days.

Let's remove 53 saturdays and 52 sundays. It remains 260 days.

Now, let's remove 5 public holidays that do not fall during a weekend and we obtain 255 working days in 1921.

Here is the list of these 5 public holidays:

1. Iseseisvuspäev : Thursday, 24 February, 1921
2. Suur Reede : Friday, 25 March, 1921
3. Võidupüha : Thursday, 23 June, 1921
4. Jaanipäev : Friday, 24 June, 1921
5. Teine jõulupüha : Monday, 26 December, 1921

And here are the 7 public holidays falling on a weekend:

1. Uusaasta : Saturday, 1 January, 1921
2. Ülestõusmispühad : Sunday, 27 March, 1921
3. Kevadpüha : Sunday, 1 May, 1921
4. Nelipühad : Sunday, 15 May, 1921
5. Taasiseseisvumispäev : Saturday, 20 August, 1921
6. Jõululaupäev : Saturday, 24 December, 1921
7. Esimene jõulupüha : Sunday, 25 December, 1921