Define a period

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How many working days in year 1997?

Here is the detail of the calculation:

Because 1997 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 1997.

Here is the list of these 8 public holidays:

1. Purim : Sunday, 23 March, 1997
2. Pesach : Tuesday, 22 April, 1997
3. Shvi'i shel Pesach : Monday, 28 April, 1997
4. Yom Ha-Atzmaut : Monday, 12 May, 1997
5. Shavuot : Wednesday, 11 June, 1997
6. Rosh Hashanah : Thursday, 2 October, 1997
7. Sukkot : Thursday, 16 October, 1997
8. Shemini Atzeret / Simchat Torah : Thursday, 23 October, 1997

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

1. Rosh Hashanah : Friday, 3 October, 1997
2. Yom Kippur : Saturday, 11 October, 1997