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How many working days in year 1991?

Here is the detail of the calculation:

Because 1991 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 1991.

Here is the list of these 7 public holidays:

1. Yom Ha-Atzmaut : четверг, 18 апрель, 1991
2. Shavuot : воскресенье, 19 май, 1991
3. Rosh Hashanah : понедельник, 9 сентябрь, 1991
4. Rosh Hashanah : вторник, 10 сентябрь, 1991
5. Yom Kippur : среда, 18 сентябрь, 1991
6. Sukkot : понедельник, 23 сентябрь, 1991
7. Shemini Atzeret / Simchat Torah : понедельник, 30 сентябрь, 1991

And here are the 2 public holidays falling on a weekend:

1. Pesach : суббота, 30 март, 1991
2. Shvi'i shel Pesach : пятница, 5 апрель, 1991