Define a period

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How many working days in year 1917?

Here is the detail of the calculation:

Because 1917 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 7 public holidays that do not fall during a weekend and we obtain 254 working days in 1917.

Here is the list of these 7 public holidays:

1. Uusaasta : Monday, 1 January, 1917
2. Suur Reede : Friday, 6 April, 1917
3. Kevadpüha : Tuesday, 1 May, 1917
4. Taasiseseisvumispäev : Monday, 20 August, 1917
5. Jõululaupäev : Monday, 24 December, 1917
6. Esimene jõulupüha : Tuesday, 25 December, 1917
7. Teine jõulupüha : Wednesday, 26 December, 1917

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

1. Iseseisvuspäev : Saturday, 24 February, 1917
2. Ülestõusmispühad : Sunday, 8 April, 1917
3. Nelipühad : Sunday, 27 May, 1917
4. Võidupüha : Saturday, 23 June, 1917
5. Jaanipäev : Sunday, 24 June, 1917