Define a period

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How many working days in year 1973?

Here is the detail of the calculation:

Because 1973 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 8 public holidays that do not fall during a weekend and we obtain 253 working days in 1973.

Here is the list of these 8 public holidays:

1. Uudenvuodenpäivä : Monday, 1 January, 1973
2. Pitkäperjantai : Friday, 20 April, 1973
3. 2. pääsiäispäivä : Monday, 23 April, 1973
4. Vappu : Tuesday, 1 May, 1973
5. Helatorstai : Thursday, 31 May, 1973
6. Itsenäisyyspäivä : Thursday, 6 December, 1973
7. Joulupäivä : Tuesday, 25 December, 1973
8. Tapaninpäivä : Wednesday, 26 December, 1973

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

1. Loppiainen : Saturday, 6 January, 1973
2. Pääsiäispäivä : Sunday, 22 April, 1973
3. Helluntaipäivä : Sunday, 10 June, 1973
4. Juhannuspäivä : Saturday, 23 June, 1973
5. Pyhäinpäivä : Saturday, 3 November, 1973