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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 10 public holidays that do not fall during a weekend and we obtain 251 working days in 1918.

Here is the list of these 10 public holidays:

1. New Year's Day : вторник, 1 январь, 1918
2. St. Patrick's Day (substitute day) : понедельник, 18 март, 1918
3. Good Friday : пятница, 29 март, 1918
4. Easter Monday : понедельник, 1 апрель, 1918
5. Early May Bank Holiday : понедельник, 6 май, 1918
6. Spring Bank Holiday : понедельник, 27 май, 1918
7. Orangemen's Day : пятница, 12 июль, 1918
8. Late Summer Bank Holiday : понедельник, 26 август, 1918
9. Christmas Day : среда, 25 декабрь, 1918
10. Boxing Day : четверг, 26 декабрь, 1918

And here is the public holiday falling on a weekend:

1. St. Patrick's Day : воскресенье, 17 март, 1918