Define a period

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How many working days in year 1972?

Here is the detail of the calculation:

Because 1972 is a leap year, it has 366 days.

Let's remove 53 saturdays and 53 sundays. It remains 260 days.

Now, let's remove 11 public holidays that do not fall during a weekend and we obtain 249 working days in 1972.

Here is the list of these 11 public holidays:

1. Ziua Unirii Principatelor Române : Monday, 24 January, 1972
2. Vinerea Mare : Friday, 7 April, 1972
3. A doua zi de Paște : Monday, 10 April, 1972
4. Ziua Muncii : Monday, 1 May, 1972
5. A doua zi de Rusalii : Monday, 29 May, 1972
6. Ziua Copilului : Thursday, 1 June, 1972
7. Adormirea Maicii Domnului : Tuesday, 15 August, 1972
8. Sfântul Andrei : Thursday, 30 November, 1972
9. Ziua Națională a României : Friday, 1 December, 1972
10. Crăciunul : Monday, 25 December, 1972
11. A doua zi de Crăciun : Tuesday, 26 December, 1972

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

1. Anul Nou : Saturday, 1 January, 1972
2. A doua zi după Anul Nou : Sunday, 2 January, 1972
3. Paște ortodox : Sunday, 9 April, 1972
4. Rusalii : Sunday, 28 May, 1972