Define a period

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How many working days in year 1970?

Here is the detail of the calculation:

Because 1970 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 1970.

Here is the list of these 11 public holidays:

1. New Year's Day : Thursday, 1 January, 1970
2. Day after New Year's Day : Friday, 2 January, 1970
3. Auckland Day : Monday, 26 January, 1970
4. Waitangi Day : Friday, 6 February, 1970
5. Good Friday : Friday, 27 March, 1970
6. Easter Monday : Monday, 30 March, 1970
7. Anzac Day Observance : Monday, 27 April, 1970
8. Queen's Birthday : Monday, 1 June, 1970
9. Labour Day : Monday, 26 October, 1970
10. Christmas Day : Friday, 25 December, 1970
11. Boxing Day Observance : Monday, 28 December, 1970

And here are the 2 public holidays falling on a weekend:

1. Anzac Day : Saturday, 25 April, 1970
2. Boxing Day : Saturday, 26 December, 1970