The answer is that there is no way to find out. Not all martial arts schools that offer or promote to black belt, record and report this information. Even those that do, do not all report to the same institutions or organizations. To further complicate the question, many organizations do not consider others to be credible and do not recognize their ranking system and practitioners. To add another layer to the onion, anyone can go into any Martial Arts supply store and purchase any belt they want and go about proclaiming to be any rank they choose. Another layer, the many varied styles and types of martial arts.
This question simply cannot be answered with any degree of accuracy or accepted results.
In this expert's opinion, I would say about 1%. The rest just think they do.
Actually, there would be no way to determine an accurate answer to this since there are a large number of people who would claim they know "some" yet might have only taken a few lessons, or watched enough Martial Art on television, movies, or YouTube to become "experts."
There would also be the difficulty of defining a Martial Art. Some people believe sports like boxing, or Wrestling, cage fighting, MMA are Martial Arts while others don't. You would also have to consider all the former students as well as active practitioners.
Since each recognized Martial Art system is probably represented by a number of different established organizations as well as independent schools, and none of them publish complete records, nor compile a master list shared between all organizations and systems, no one really knows.
There are tens of thousands of karate students in the US alone.
there are many different types of karate and they are all created by different people
I don't know but I know that Karate, Ninjitsu (It is a real thing) and early Jijitsu came from there so probably a lot.
{| |- | The origins of karate are shrouded in the mist of time. The roots go back many hundreds of years. The Chinese came to Okinawa and brought with them kung fu. It was combined with the native art of Te and became karate. |}
There are many different styles of martial arts all of which have some influence from the region they came from. Karate for example incorporates some of the Southern based style of Chinese martial arts(MA).
1000000
kung fu, tai kuan-do, karate, judo, dujissu and fung-swai
Karate is a martial art. The meaning is open hand or China hand. It originated in Okinawa many centuries ago as a combination of Chinese Kung Fu and Okinawan wrestling.
Monks are not thought to have created karate. There were some that went to Okinawa and taught some aspects of Kung Fu to the Ryu Kyu King's guards that were merged into the local wrestling to create what we now know as karate.
As far as I know (from listening in karate class) martial arts started in China and were brought to Japan along with calligraphy and art. However, the stereotypical, "karate" (there are many many different forms) was "invented" in Japan.
That would be none, as Karate is not an Olympic sport. Taekwondo is in the Olympics.
because they think they will be cool