Define a period

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How many working days in year 1913?

Here is the detail of the calculation:

Because 1913 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 10 public holidays that do not fall during a weekend and we obtain 251 working days in 1913.

Here is the list of these 10 public holidays:

1. Uusaasta : Wednesday, 1 January, 1913
2. Iseseisvuspäev : Monday, 24 February, 1913
3. Suur Reede : Friday, 21 March, 1913
4. Kevadpüha : Thursday, 1 May, 1913
5. Võidupüha : Monday, 23 June, 1913
6. Jaanipäev : Tuesday, 24 June, 1913
7. Taasiseseisvumispäev : Wednesday, 20 August, 1913
8. Jõululaupäev : Wednesday, 24 December, 1913
9. Esimene jõulupüha : Thursday, 25 December, 1913
10. Teine jõulupüha : Friday, 26 December, 1913

And here are the 2 public holidays falling on a weekend:

1. Ülestõusmispühad : Sunday, 23 March, 1913
2. Nelipühad : Sunday, 11 May, 1913