Define a period

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How many working days in year 1971?

Here is the detail of the calculation:

Because 1971 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 7 public holidays that do not fall during a weekend and we obtain 253 working days in 1971.

Here is the list of these 7 public holidays:

1. Yom Ha-Atzmaut : Thursday, 29 April, 1971
2. Shavuot : Sunday, 30 May, 1971
3. Rosh Hashanah : Monday, 20 September, 1971
4. Rosh Hashanah : Tuesday, 21 September, 1971
5. Yom Kippur : Wednesday, 29 September, 1971
6. Sukkot : Monday, 4 October, 1971
7. Shemini Atzeret / Simchat Torah : Monday, 11 October, 1971

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

1. Pesach : Saturday, 10 April, 1971
2. Shvi'i shel Pesach : Friday, 16 April, 1971