Define a period

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How many working days in year 2000?

Here is the detail of the calculation:

Because 2000 is a leap year, it has 366 days.

Let's remove 52 saturdays and 53 sundays. It remains 261 days.

Now, let's remove 6 public holidays that do not fall during a weekend and we obtain 255 working days in 2000.

Here is the list of these 6 public holidays:

1. Purim : Tuesday, 21 March, 2000
2. Pesach : Thursday, 20 April, 2000
3. Shvi'i shel Pesach : Wednesday, 26 April, 2000
4. Yom Ha-Atzmaut : Wednesday, 10 May, 2000
5. Rosh Hashanah : Sunday, 1 October, 2000
6. Yom Kippur : Monday, 9 October, 2000

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

1. Shavuot : Friday, 9 June, 2000
2. Rosh Hashanah : Saturday, 30 September, 2000
3. Sukkot : Saturday, 14 October, 2000
4. Shemini Atzeret / Simchat Torah : Saturday, 21 October, 2000