Define a period

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How many working days in year 1956?

Here is the detail of the calculation:

Because 1956 is a leap year, it has 366 days.

Let's remove 52 saturdays and 53 sundays. It remains 261 days.

Now, let's remove 11 public holidays that do not fall during a weekend and we obtain 250 working days in 1956.

Here is the list of these 11 public holidays:

1. Нова година : Monday, 2 January, 1956
2. Национален ден (наблюдаван) : Monday, 5 March, 1956
3. Ден на труда : Tuesday, 1 May, 1956
4. Православни Велики петък : Friday, 4 May, 1956
5. Православни Велики понеделник : Monday, 7 May, 1956
6. Ден на културата и славянската писменост : Thursday, 24 May, 1956
7. Ден на съединението : Thursday, 6 September, 1956
8. Ден на независимостта (наблюдаван) : Monday, 24 September, 1956
9. Бъдни вечер : Monday, 24 December, 1956
10. Коледа : Tuesday, 25 December, 1956
11. Втори ден на Коледа : Wednesday, 26 December, 1956

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

1. Нова година : Sunday, 1 January, 1956
2. Национален ден : Saturday, 3 March, 1956
3. Православна Велика събота : Saturday, 5 May, 1956
4. Православен Великден : Sunday, 6 May, 1956
5. Ден на независимостта : Saturday, 22 September, 1956