Define a period

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How many working days in year 1988?

Here is the detail of the calculation:

Because 1988 is a leap year, it has 366 days.

Let's remove 53 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 1988.

Here is the list of these 6 public holidays:

1. Новы год : Friday, 1 January, 1988
2. Каляды праваслаўныя : Thursday, 7 January, 1988
3. Мiжнародны жаночы дзень : Tuesday, 8 March, 1988
4. Радунiца : Tuesday, 19 April, 1988
5. Дзень Перамогi : Monday, 9 May, 1988
6. Дзень Кастрычніцкай рэвалюцыі : Monday, 7 November, 1988

And here are the 4 public holidays falling on a weekend:

1. Новы год : Saturday, 2 January, 1988
2. Дзень працы : Sunday, 1 May, 1988
3. Дзень Незалежнасцi : Sunday, 3 July, 1988
4. Каляды каталiцкiя : Sunday, 25 December, 1988