Define a period

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How many working days in year 1983?

Here is the detail of the calculation:

Because 1983 is not a leap year, it has 365 days.

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

Now, let's remove 11 public holidays that do not fall during a weekend and we obtain 249 working days in 1983.

Here is the list of these 11 public holidays:

1. New Year's Day Observance : Monday, 3 January, 1983
2. Day after New Year's Day Observance : Tuesday, 4 January, 1983
3. Auckland Day : Monday, 31 January, 1983
4. Waitangi Day Observance : Monday, 7 February, 1983
5. Good Friday : Friday, 1 April, 1983
6. Easter Monday : Monday, 4 April, 1983
7. Anzac Day : Monday, 25 April, 1983
8. Queen's Birthday : Monday, 6 June, 1983
9. Labour Day : Monday, 24 October, 1983
10. Boxing Day : Monday, 26 December, 1983
11. Christmas Day Observance : Tuesday, 27 December, 1983

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

1. New Year's Day : Saturday, 1 January, 1983
2. Day after New Year's Day : Sunday, 2 January, 1983
3. Waitangi Day : Sunday, 6 February, 1983
4. Christmas Day : Sunday, 25 December, 1983