What percentage of presidents served in the ...

By simply putting your question into a search engine such as Google you would be able to find your answer. By posting in a forum such as this, especially when posted under the topic of President, you will start numerous political fights. People will immediately feel that you are asking your question in a rhetorical manner and that all you are trying to do is start another fight. They will be paranoid that you might be attacking their guy and that they must then come directly to his aid by answering your question in a snide and attacking manner.

Next time you have a question, Google it first. You'll get the answer you want without starting a fight. Now here is your answer, which I found on Google by asking your exact question. By the way, it's roughly 75%.

http://en.wikipedia.org/wiki/List_of_United_States_Presidents_by_military_service

The ONLY President I know of that didn't serve in ther military was Clinton.  He ruined the nation, sent brave men to fight in the Balkans, insulted Vietnam veterans at the memorial for troops who died in a war that Cowardly Clinton fled his homeland to avoid. 

Am I alone in thinking that we need a Commander In Chief who has military experience?  Obama bin Laden, like Clinton, never served in the military so he has a surly attitude to veterans and like Clinton before him, will do everything in his power to persecute anyone brave enough to do what he refused to do.

McCain served with distinction as a Navy A-4 pilot, was shot down over South Vietnam, and was held as a Prisoner of War.  He came back and worked really hard in his office, a lesson he learned at Annapolis.

Only a veteran knows enough about international diplomacy to avoid the traps that lead to war.

Think about it.