Define a period

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How many working days in year 1988?

Here is the detail of the calculation:

Because 1988 is a leap year, it has 366 days.

Let's remove 53 saturdays and 53 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 1988.

Here is the list of these 7 public holidays:

1. יום העצמאות : Thursday, 21 April, 1988
2. שבועות : Sunday, 22 May, 1988
3. ראש השנה : Monday, 12 September, 1988
4. ראש השנה : Tuesday, 13 September, 1988
5. יום כיפור : Wednesday, 21 September, 1988
6. סוכות : Monday, 26 September, 1988
7. שמחת תורה/שמיני עצרת : Monday, 3 October, 1988

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

1. פסח : Saturday, 2 April, 1988
2. שביעי של פסח : Friday, 8 April, 1988