Define a period

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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 5 public holidays that do not fall during a weekend and we obtain 255 working days in 1983.

Here is the list of these 5 public holidays:

1. Каляды праваслаўныя : Friday, 7 January, 1983
2. Мiжнародны жаночы дзень : Tuesday, 8 March, 1983
3. Дзень Перамогi : Monday, 9 May, 1983
4. Радунiца : Tuesday, 17 May, 1983
5. Дзень Кастрычніцкай рэвалюцыі : Monday, 7 November, 1983

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

1. Новы год : Saturday, 1 January, 1983
2. Новы год : Sunday, 2 January, 1983
3. Дзень працы : Sunday, 1 May, 1983
4. Дзень Незалежнасцi : Sunday, 3 July, 1983
5. Каляды каталiцкiя : Sunday, 25 December, 1983