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 9 public holidays that do not fall during a weekend and we obtain 252 working days in 1988.

Here is the list of these 9 public holidays:

1. Restoration Day of the Independent Czech State : Friday, 1 January, 1988
2. Good Friday : Friday, 1 April, 1988
3. Easter Monday : Monday, 4 April, 1988
4. St Cyril and Methodius' Day : Tuesday, 5 July, 1988
5. Jan Hus Day : Wednesday, 6 July, 1988
6. St Wenceslas Day : Wednesday, 28 September, 1988
7. Independence Day : Friday, 28 October, 1988
8. Freedom and Democracy Day : Thursday, 17 November, 1988
9. St. Stephen's Day : Monday, 26 December, 1988

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

1. Labour Day : Sunday, 1 May, 1988
2. Liberation Day : Sunday, 8 May, 1988
3. Christmas Eve : Saturday, 24 December, 1988
4. Christmas Day : Sunday, 25 December, 1988