Define a period

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How many working days in year 1918?

Here is the detail of the calculation:

Because 1918 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 8 public holidays that do not fall during a weekend and we obtain 253 working days in 1918.

Here is the list of these 8 public holidays:

1. Uusaasta : Tuesday, 1 January, 1918
2. Suur Reede : Friday, 29 March, 1918
3. Kevadpüha : Wednesday, 1 May, 1918
4. Jaanipäev : Monday, 24 June, 1918
5. Taasiseseisvumispäev : Tuesday, 20 August, 1918
6. Jõululaupäev : Tuesday, 24 December, 1918
7. Esimene jõulupüha : Wednesday, 25 December, 1918
8. Teine jõulupüha : Thursday, 26 December, 1918

And here are the 4 public holidays falling on a weekend:

1. Iseseisvuspäev : Sunday, 24 February, 1918
2. Ülestõusmispühad : Sunday, 31 March, 1918
3. Nelipühad : Sunday, 19 May, 1918
4. Võidupüha : Sunday, 23 June, 1918