Define a period

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How many working days in year 1960?

Here is the detail of the calculation:

Because 1960 is a leap year, it has 366 days.

Let's remove 53 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 1960.

Here is the list of these 11 public holidays:

1. New Year's Day : Friday, 1 January, 1960
2. Day after New Year's Day Observance : Monday, 4 January, 1960
3. Auckland Day : Monday, 1 February, 1960
4. Waitangi Day Observance : Monday, 8 February, 1960
5. Good Friday : Friday, 15 April, 1960
6. Easter Monday : Monday, 18 April, 1960
7. Anzac Day : Monday, 25 April, 1960
8. Queen's Birthday : Monday, 6 June, 1960
9. Labour Day : Monday, 24 October, 1960
10. Boxing Day : Monday, 26 December, 1960
11. Christmas Day Observance : Tuesday, 27 December, 1960

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

1. Day after New Year's Day : Saturday, 2 January, 1960
2. Waitangi Day : Saturday, 6 February, 1960
3. Christmas Day : Sunday, 25 December, 1960