Define a period

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How many working days in year 1990?

Here is the detail of the calculation:

Because 1990 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 12 public holidays that do not fall during a weekend and we obtain 249 working days in 1990.

Here is the list of these 12 public holidays:

1. Anul Nou : Monday, 1 January, 1990
2. A doua zi după Anul Nou : Tuesday, 2 January, 1990
3. Ziua Unirii Principatelor Române : Wednesday, 24 January, 1990
4. Vinerea Mare : Friday, 13 April, 1990
5. A doua zi de Paște : Monday, 16 April, 1990
6. Ziua Muncii : Tuesday, 1 May, 1990
7. Ziua Copilului : Friday, 1 June, 1990
8. A doua zi de Rusalii : Monday, 4 June, 1990
9. Adormirea Maicii Domnului : Wednesday, 15 August, 1990
10. Sfântul Andrei : Friday, 30 November, 1990
11. Crăciunul : Tuesday, 25 December, 1990
12. A doua zi de Crăciun : Wednesday, 26 December, 1990

And here are the 3 public holidays falling on a weekend:

1. Paște ortodox : Sunday, 15 April, 1990
2. Rusalii : Sunday, 3 June, 1990
3. Ziua Națională a României : Saturday, 1 December, 1990