Define a period

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How many working days in year 1916?

Here is the detail of the calculation:

Because 1916 is a leap year, it has 366 days.

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

Now, let's remove 6 public holidays that do not fall during a weekend and we obtain 254 working days in 1916.

Here is the list of these 6 public holidays:

1. Iseseisvuspäev : Thursday, 24 February, 1916
2. Suur Reede : Friday, 21 April, 1916
3. Kevadpüha : Monday, 1 May, 1916
4. Võidupüha : Friday, 23 June, 1916
5. Esimene jõulupüha : Monday, 25 December, 1916
6. Teine jõulupüha : Tuesday, 26 December, 1916

And here are the 6 public holidays falling on a weekend:

1. Uusaasta : Saturday, 1 January, 1916
2. Ülestõusmispühad : Sunday, 23 April, 1916
3. Nelipühad : Sunday, 11 June, 1916
4. Jaanipäev : Saturday, 24 June, 1916
5. Taasiseseisvumispäev : Sunday, 20 August, 1916
6. Jõululaupäev : Sunday, 24 December, 1916