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How many working days in year 1999?

Here is the detail of the calculation:

Because 1999 is not a leap year, it has 365 days.

Let's remove 53 saturdays and 52 sundays. It remains 260 days.

Now, let's remove 5 public holidays that do not fall during a weekend and we obtain 255 working days in 1999.

Here is the list of these 5 public holidays:

1. Pesach : четверг, 1 апрель, 1999
2. Shvi'i shel Pesach : среда, 7 апрель, 1999
3. Yom Ha-Atzmaut : среда, 21 апрель, 1999
4. Rosh Hashanah : воскресенье, 12 сентябрь, 1999
5. Yom Kippur : понедельник, 20 сентябрь, 1999

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

1. Shavuot : пятница, 21 май, 1999
2. Rosh Hashanah : суббота, 11 сентябрь, 1999
3. Sukkot : суббота, 25 сентябрь, 1999
4. Shemini Atzeret / Simchat Torah : суббота, 2 октябрь, 1999