Define a period

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How many working days in year 1977?

Here is the detail of the calculation:

Because 1977 is not a leap year, it has 365 days.

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

Now, let's remove 8 public holidays that do not fall during a weekend and we obtain 252 working days in 1977.

Here is the list of these 8 public holidays:

1. פסח : Sunday, 3 April, 1977
2. יום העצמאות : Thursday, 21 April, 1977
3. שבועות : Monday, 23 May, 1977
4. ראש השנה : Tuesday, 13 September, 1977
5. ראש השנה : Wednesday, 14 September, 1977
6. יום כיפור : Thursday, 22 September, 1977
7. סוכות : Tuesday, 27 September, 1977
8. שמחת תורה/שמיני עצרת : Tuesday, 4 October, 1977

And here is the public holiday falling on a weekend:

1. שביעי של פסח : Saturday, 9 April, 1977