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How many working days in year 1989?

Here is the detail of the calculation:

Because 1989 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 6 public holidays that do not fall during a weekend and we obtain 255 working days in 1989.

Here is the list of these 6 public holidays:

1. Purim : вторник, 21 март, 1989
2. Pesach : четверг, 20 апрель, 1989
3. Shvi'i shel Pesach : среда, 26 апрель, 1989
4. Yom Ha-Atzmaut : среда, 10 май, 1989
5. Rosh Hashanah : воскресенье, 1 октябрь, 1989
6. Yom Kippur : понедельник, 9 октябрь, 1989

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

1. Shavuot : пятница, 9 июнь, 1989
2. Rosh Hashanah : суббота, 30 сентябрь, 1989
3. Sukkot : суббота, 14 октябрь, 1989
4. Shemini Atzeret / Simchat Torah : суббота, 21 октябрь, 1989