Define a period

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How many working days in year 1978?

Here is the detail of the calculation:

Because 1978 is not a leap year, it has 365 days.

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

Now, let's remove 9 public holidays that do not fall during a weekend and we obtain 251 working days in 1978.

Here is the list of these 9 public holidays:

1. Easter Monday : Monday, 27 March, 1978
2. Labour Day : Monday, 1 May, 1978
3. Ascension Day : Thursday, 4 May, 1978
4. Whit Monday : Monday, 15 May, 1978
5. National Day : Friday, 23 June, 1978
6. Assumption of Mary : Tuesday, 15 August, 1978
7. All Saints' Day : Wednesday, 1 November, 1978
8. Christmas Day : Monday, 25 December, 1978
9. St. Stephen's Day : Tuesday, 26 December, 1978

And here is the public holiday falling on a weekend:

1. New Year's Day : Sunday, 1 January, 1978