Define a period

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How many working days in year 1981?

Here is the detail of the calculation:

Because 1981 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 1981.

Here is the list of these 10 public holidays:

1. Anul Nou : Thursday, 1 January, 1981
2. A doua zi după Anul Nou : Friday, 2 January, 1981
3. Vinerea Mare : Friday, 24 April, 1981
4. A doua zi de Paște : Monday, 27 April, 1981
5. Ziua Muncii : Friday, 1 May, 1981
6. Ziua Copilului : Monday, 1 June, 1981
7. A doua zi de Rusalii : Monday, 15 June, 1981
8. Sfântul Andrei : Monday, 30 November, 1981
9. Ziua Națională a României : Tuesday, 1 December, 1981
10. Crăciunul : Friday, 25 December, 1981

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

1. Ziua Unirii Principatelor Române : Saturday, 24 January, 1981
2. Paște ortodox : Sunday, 26 April, 1981
3. Rusalii : Sunday, 14 June, 1981
4. Adormirea Maicii Domnului : Saturday, 15 August, 1981
5. A doua zi de Crăciun : Saturday, 26 December, 1981