Define a period

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How many working days in year 1986?

Here is the detail of the calculation:

Because 1986 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 9 public holidays that do not fall during a weekend and we obtain 252 working days in 1986.

Here is the list of these 9 public holidays:

1. Новы год : Wednesday, 1 January, 1986
2. Новы год : Thursday, 2 January, 1986
3. Каляды праваслаўныя : Tuesday, 7 January, 1986
4. Дзень працы : Thursday, 1 May, 1986
5. Дзень Перамогi : Friday, 9 May, 1986
6. Радунiца : Tuesday, 13 May, 1986
7. Дзень Незалежнасцi : Thursday, 3 July, 1986
8. Дзень Кастрычніцкай рэвалюцыі : Friday, 7 November, 1986
9. Каляды каталiцкiя : Thursday, 25 December, 1986

And here is the public holiday falling on a weekend:

1. Мiжнародны жаночы дзень : Saturday, 8 March, 1986