Define a period

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How many working days in year 1972?

Here is the detail of the calculation:

Because 1972 is a leap year, it has 366 days.

Let's remove 53 saturdays and 53 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 1972.

Here is the list of these 11 public holidays:

1. New Year's Day Observance : Monday, 3 January, 1972
2. Day after New Year's Day Observance : Tuesday, 4 January, 1972
3. Auckland Day : Monday, 31 January, 1972
4. Waitangi Day Observance : Monday, 7 February, 1972
5. Good Friday : Friday, 31 March, 1972
6. Easter Monday : Monday, 3 April, 1972
7. Anzac Day : Tuesday, 25 April, 1972
8. Queen's Birthday : Monday, 5 June, 1972
9. Labour Day : Monday, 23 October, 1972
10. Christmas Day : Monday, 25 December, 1972
11. Boxing Day : Tuesday, 26 December, 1972

And here are the 3 public holidays falling on a weekend:

1. New Year's Day : Saturday, 1 January, 1972
2. Day after New Year's Day : Sunday, 2 January, 1972
3. Waitangi Day : Sunday, 6 February, 1972