Define a period

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How many working days in year 1931?

Here is the detail of the calculation:

Because 1931 is not a leap year, it has 365 days.

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

Now, let's remove 9 public holidays that do not fall during a weekend and we obtain 252 working days in 1931.

Here is the list of these 9 public holidays:

1. Uusaasta : Thursday, 1 January, 1931
2. Iseseisvuspäev : Tuesday, 24 February, 1931
3. Suur Reede : Friday, 3 April, 1931
4. Kevadpüha : Friday, 1 May, 1931
5. Võidupüha : Tuesday, 23 June, 1931
6. Jaanipäev : Wednesday, 24 June, 1931
7. Taasiseseisvumispäev : Thursday, 20 August, 1931
8. Jõululaupäev : Thursday, 24 December, 1931
9. Esimene jõulupüha : Friday, 25 December, 1931

And here are the 3 public holidays falling on a weekend:

1. Ülestõusmispühad : Sunday, 5 April, 1931
2. Nelipühad : Sunday, 24 May, 1931
3. Teine jõulupüha : Saturday, 26 December, 1931