Define a period

...

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. New Year's Day : Friday, 1 January, 1988
2. Good Friday : Friday, 1 April, 1988
3. Easter Monday : Monday, 4 April, 1988
4. Ascension Day : Thursday, 12 May, 1988
5. Pentecost Monday : Monday, 23 May, 1988
6. Boxing Day : Monday, 26 December, 1988

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

1. Easter Sunday : Sunday, 3 April, 1988
2. Queen's Day : Saturday, 30 April, 1988
3. Pentecost Sunday : Sunday, 22 May, 1988
4. Christmas Day : Sunday, 25 December, 1988