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How many working days in year 2020?

Here is the detail of the calculation:

Because 2020 is a leap year, it has 366 days.

Let's remove 52 saturdays and 52 sundays. It remains 262 days.

Now, let's remove 5 public holidays that do not fall during a weekend and we obtain 257 working days in 2020.

Here is the list of these 5 public holidays:

1. Pesach : четверг, 9 апрель, 2020
2. Shvi'i shel Pesach : среда, 15 апрель, 2020
3. Yom Ha-Atzmaut : среда, 29 апрель, 2020
4. Rosh Hashanah : воскресенье, 20 сентябрь, 2020
5. Yom Kippur : понедельник, 28 сентябрь, 2020

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

1. Shavuot : пятница, 29 май, 2020
2. Rosh Hashanah : суббота, 19 сентябрь, 2020
3. Sukkot : суббота, 3 октябрь, 2020
4. Shemini Atzeret / Simchat Torah : суббота, 10 октябрь, 2020