Define a period

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How many working days in year 1951?

Here is the detail of the calculation:

Because 1951 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 1951.

Here is the list of these 12 public holidays:

1. Нова година : Monday, 1 January, 1951
2. Национален ден (наблюдаван) : Monday, 5 March, 1951
3. Православни Велики петък : Friday, 27 April, 1951
4. Православни Велики понеделник : Monday, 30 April, 1951
5. Ден на труда : Tuesday, 1 May, 1951
6. Гергьовден (наблюдаван) : Monday, 7 May, 1951
7. Ден на културата и славянската писменост : Thursday, 24 May, 1951
8. Ден на съединението : Thursday, 6 September, 1951
9. Ден на независимостта (наблюдаван) : Monday, 24 September, 1951
10. Бъдни вечер : Monday, 24 December, 1951
11. Коледа : Tuesday, 25 December, 1951
12. Втори ден на Коледа : Wednesday, 26 December, 1951

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

1. Национален ден : Saturday, 3 March, 1951
2. Православна Велика събота : Saturday, 28 April, 1951
3. Православен Великден : Sunday, 29 April, 1951
4. Гергьовден : Sunday, 6 May, 1951
5. Ден на независимостта : Saturday, 22 September, 1951