Define a period

...

How many working days in year 1983?

Here is the detail of the calculation:

Because 1983 is not a leap year, it has 365 days.

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

Now, let's remove 6 public holidays that do not fall during a weekend and we obtain 254 working days in 1983.

Here is the list of these 6 public holidays:

1. Loppiainen : Thursday, 6 January, 1983
2. Pitkäperjantai : Friday, 1 April, 1983
3. 2. pääsiäispäivä : Monday, 4 April, 1983
4. Helatorstai : Thursday, 12 May, 1983
5. Itsenäisyyspäivä : Tuesday, 6 December, 1983
6. Tapaninpäivä : Monday, 26 December, 1983

And here are the 7 public holidays falling on a weekend:

1. Uudenvuodenpäivä : Saturday, 1 January, 1983
2. Pääsiäispäivä : Sunday, 3 April, 1983
3. Vappu : Sunday, 1 May, 1983
4. Helluntaipäivä : Sunday, 22 May, 1983
5. Juhannuspäivä : Saturday, 25 June, 1983
6. Pyhäinpäivä : Saturday, 5 November, 1983
7. Joulupäivä : Sunday, 25 December, 1983