David Letterman – 120

American TV show host, producer, writer, and comedian David Michael Letterman is the host of late-night TV talk shows for the past 33 years. Born on April 12, 1947, in Indianapolis, Indiana, Letterman was the son of a florist and a church secretary. His move to Los Angeles was encouraged by his ex-wife Michelle and some of his fraternity brothers in Sigma Chi. He had high hopes of becoming a comedy writer upon moving to LA.

He started his career on February 1, 1982, on Late Night with David Letterman on NBC, and it ended on May 20, 2015. He hosted the Late Night and Late Show for 6,080 episodes, surpassing his mentor and friend Johnny Carson as the longest-serving late-night talk show host in the history of American television. If you didn’t know yet, Letterman has an IQ of 120, which is, on average, the 90th percentile of intelligence, and is given credit as the most desirable long-term partner.