Define a period

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How many working days in year 1980?

Here is the detail of the calculation:

Because 1980 is a leap year, it has 366 days.

Let's remove 52 saturdays and 52 sundays. It remains 262 days.

Now, let's remove 8 public holidays that do not fall during a weekend and we obtain 254 working days in 1980.

Here is the list of these 8 public holidays:

1. New Year's Day : Tuesday, 1 January, 1980
2. Good Friday : Friday, 4 April, 1980
3. Easter Monday : Monday, 7 April, 1980
4. Labour Day : Thursday, 1 May, 1980
5. Establishment Day : Tuesday, 1 July, 1980
6. National Day : Wednesday, 1 October, 1980
7. Christmas Day : Thursday, 25 December, 1980
8. Boxing Day : Friday, 26 December, 1980

And here is the public holiday falling on a weekend:

1. Holy Saturday : Saturday, 5 April, 1980