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 8 public holidays that do not fall during a weekend and we obtain 252 working days in 1972.

Here is the list of these 8 public holidays:

1. Loppiainen : Thursday, 6 January, 1972
2. Pitkäperjantai : Friday, 31 March, 1972
3. 2. pääsiäispäivä : Monday, 3 April, 1972
4. Vappu : Monday, 1 May, 1972
5. Helatorstai : Thursday, 11 May, 1972
6. Itsenäisyyspäivä : Wednesday, 6 December, 1972
7. Joulupäivä : Monday, 25 December, 1972
8. Tapaninpäivä : Tuesday, 26 December, 1972

And here are the 5 public holidays falling on a weekend:

1. Uudenvuodenpäivä : Saturday, 1 January, 1972
2. Pääsiäispäivä : Sunday, 2 April, 1972
3. Helluntaipäivä : Sunday, 21 May, 1972
4. Juhannuspäivä : Saturday, 24 June, 1972
5. Pyhäinpäivä : Saturday, 4 November, 1972