Define a period

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How many working days in year 1999?

Here is the detail of the calculation:

Because 1999 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 6 public holidays that do not fall during a weekend and we obtain 255 working days in 1999.

Here is the list of these 6 public holidays:

1. Uudenvuodenpäivä : Friday, 1 January, 1999
2. Loppiainen : Wednesday, 6 January, 1999
3. Pitkäperjantai : Friday, 2 April, 1999
4. 2. pääsiäispäivä : Monday, 5 April, 1999
5. Helatorstai : Thursday, 13 May, 1999
6. Itsenäisyyspäivä : Monday, 6 December, 1999

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

1. Pääsiäispäivä : Sunday, 4 April, 1999
2. Vappu : Saturday, 1 May, 1999
3. Helluntaipäivä : Sunday, 23 May, 1999
4. Juhannuspäivä : Saturday, 26 June, 1999
5. Pyhäinpäivä : Saturday, 6 November, 1999
6. Joulupäivä : Saturday, 25 December, 1999
7. Tapaninpäivä : Sunday, 26 December, 1999