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How many working days in year 1981?

Here is the detail of the calculation:

Because 1981 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 1981.

Here is the list of these 8 public holidays:

1. Pesach : воскресенье, 19 апрель, 1981
2. Yom Ha-Atzmaut : четверг, 7 май, 1981
3. Shavuot : понедельник, 8 июнь, 1981
4. Rosh Hashanah : вторник, 29 сентябрь, 1981
5. Rosh Hashanah : среда, 30 сентябрь, 1981
6. Yom Kippur : четверг, 8 октябрь, 1981
7. Sukkot : вторник, 13 октябрь, 1981
8. Shemini Atzeret / Simchat Torah : вторник, 20 октябрь, 1981

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

1. Purim : пятница, 20 март, 1981
2. Shvi'i shel Pesach : суббота, 25 апрель, 1981