RE: 400 out of how many?
SEE HERE:
www.statista.com/topics/1244/physicians/
In 2009, there were over 970,000 doctors of medicine all over the United States. This figure included more than 120,000 inactive and some 57,000 unclassified physicians. Thus, the U.S. has a less marked physician density compared to some other countries.
Compare that to the suicide rate in the USA.
Suicide is the 12th leading cause of death in the United States. According to the Centers for Disease Control, in the United States as of 2010, more people died of suicide than in car accidents. In 2010, the total number of suicide deaths in the United States was 38,364 ( The USA has a population of north of 300 million ).
So, the suicide rate among Physicians relative to their number in this country is MUCH HIGHER (nearly 4 times ) the national rate.
4 times almost nothing is still almost nothing. 400 out of nearly a million is, to borrow an accounting term, non-material.