Define a period

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How many working days in year 1977?

Here is the detail of the calculation:

Because 1977 is not a leap year, it has 365 days.

Let's remove 53 saturdays and 52 sundays. It remains 260 days.

Now, let's remove 9 public holidays that do not fall during a weekend and we obtain 251 working days in 1977.

Here is the list of these 9 public holidays:

1. Ziua Unirii Principatelor Române : Monday, 24 January, 1977
2. Vinerea Mare : Friday, 8 April, 1977
3. A doua zi de Paște : Monday, 11 April, 1977
4. A doua zi de Rusalii : Monday, 30 May, 1977
5. Ziua Copilului : Wednesday, 1 June, 1977
6. Adormirea Maicii Domnului : Monday, 15 August, 1977
7. Sfântul Andrei : Wednesday, 30 November, 1977
8. Ziua Națională a României : Thursday, 1 December, 1977
9. A doua zi de Crăciun : Monday, 26 December, 1977

And here are the 6 public holidays falling on a weekend:

1. Anul Nou : Saturday, 1 January, 1977
2. A doua zi după Anul Nou : Sunday, 2 January, 1977
3. Paște ortodox : Sunday, 10 April, 1977
4. Ziua Muncii : Sunday, 1 May, 1977
5. Rusalii : Sunday, 29 May, 1977
6. Crăciunul : Sunday, 25 December, 1977