Define a period

...

How many working days in year 1987?

Here is the detail of the calculation:

Because 1987 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 10 public holidays that do not fall during a weekend and we obtain 251 working days in 1987.

Here is the list of these 10 public holidays:

1. Anul Nou : Thursday, 1 January, 1987
2. A doua zi după Anul Nou : Friday, 2 January, 1987
3. Vinerea Mare : Friday, 17 April, 1987
4. A doua zi de Paște : Monday, 20 April, 1987
5. Ziua Muncii : Friday, 1 May, 1987
6. Ziua Copilului : Monday, 1 June, 1987
7. A doua zi de Rusalii : Monday, 8 June, 1987
8. Sfântul Andrei : Monday, 30 November, 1987
9. Ziua Națională a României : Tuesday, 1 December, 1987
10. Crăciunul : Friday, 25 December, 1987

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

1. Ziua Unirii Principatelor Române : Saturday, 24 January, 1987
2. Paște ortodox : Sunday, 19 April, 1987
3. Rusalii : Sunday, 7 June, 1987
4. Adormirea Maicii Domnului : Saturday, 15 August, 1987
5. A doua zi de Crăciun : Saturday, 26 December, 1987