Define a period

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How many working days in year 1979?

Here is the detail of the calculation:

Because 1979 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 5 public holidays that do not fall during a weekend and we obtain 256 working days in 1979.

Here is the list of these 5 public holidays:

1. פסח : Thursday, 12 April, 1979
2. שביעי של פסח : Wednesday, 18 April, 1979
3. יום העצמאות : Wednesday, 2 May, 1979
4. ראש השנה : Sunday, 23 September, 1979
5. יום כיפור : Monday, 1 October, 1979

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

1. שבועות : Friday, 1 June, 1979
2. ראש השנה : Saturday, 22 September, 1979
3. סוכות : Saturday, 6 October, 1979
4. שמחת תורה/שמיני עצרת : Saturday, 13 October, 1979