Define a period

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How many working days in year 1999?

Here is the detail of the calculation:

Because 1999 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 11 public holidays that do not fall during a weekend and we obtain 250 working days in 1999.

Here is the list of these 11 public holidays:

1. New Year's Day : Friday, 1 January, 1999
2. Day after New Year's Day Observance : Monday, 4 January, 1999
3. Auckland Day : Monday, 1 February, 1999
4. Waitangi Day Observance : Monday, 8 February, 1999
5. Good Friday : Friday, 2 April, 1999
6. Easter Monday : Monday, 5 April, 1999
7. Anzac Day Observance : Monday, 26 April, 1999
8. Queen's Birthday : Monday, 7 June, 1999
9. Labour Day : Monday, 25 October, 1999
10. Christmas Day Observance : Monday, 27 December, 1999
11. Boxing Day Observance : Tuesday, 28 December, 1999

And here are the 5 public holidays falling on a weekend:

1. Day after New Year's Day : Saturday, 2 January, 1999
2. Waitangi Day : Saturday, 6 February, 1999
3. Anzac Day : Sunday, 25 April, 1999
4. Christmas Day : Saturday, 25 December, 1999
5. Boxing Day : Sunday, 26 December, 1999