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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. New Year's Day : вторник, 1 январь, 1918
2. Good Friday : пятница, 29 март, 1918
3. Easter Monday : понедельник, 1 апрель, 1918
4. Queen's Day : вторник, 30 апрель, 1918
5. Ascension Day : четверг, 9 май, 1918
6. Pentecost Monday : понедельник, 20 май, 1918
7. Christmas Day : среда, 25 декабрь, 1918
8. Boxing Day : четверг, 26 декабрь, 1918

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

1. Easter Sunday : воскресенье, 31 март, 1918
2. Liberation Day : воскресенье, 5 май, 1918
3. Pentecost Sunday : воскресенье, 19 май, 1918