Define a period

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How many working days in year 1974?

Here is the detail of the calculation:

Because 1974 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 1974.

Here is the list of these 8 public holidays:

1. Pesach : Sunday, 7 April, 1974
2. Yom Ha-Atzmaut : Thursday, 25 April, 1974
3. Shavuot : Monday, 27 May, 1974
4. Rosh Hashanah : Tuesday, 17 September, 1974
5. Rosh Hashanah : Wednesday, 18 September, 1974
6. Yom Kippur : Thursday, 26 September, 1974
7. Sukkot : Tuesday, 1 October, 1974
8. Shemini Atzeret / Simchat Torah : Tuesday, 8 October, 1974

And here is the public holiday falling on a weekend:

1. Shvi'i shel Pesach : Saturday, 13 April, 1974