On Wednesday morning, Brian Thompson, CEO of $UnitedHealth(UNH)$ insurance business unit, was shot and killed outside the Hilton Hotel in Midtown New York.The incident occurred shortly before 7 a.m. EDT as Thompson was traveling to a scheduled investor meeting.He was shot in the chest by an assailant who had been waiting for him at the hotel's entrance and was pronounced dead a short time after being taken to Mount Sinai Hospital, according to reports.Police are calling the shooting a deliberate act rather than a random crime.The CEO of a $500 billion market capitalization company said no, but the most important thing for investors is what effect it will have on the stock price.Looking at the disk, the news has had little impact.UNH is a very typic