Conversation so far:
When did late night with david letterman begin?
It premiered on NBC on February 1, 1982, and concluded on June 25, 1993.
Did David Letterman have any other host with him at the time of starting Late Night with David Letterman?
All throughout 1981, in addition to guest-hosting the Tonight Show as outlined in the terms of his contract, Letterman also frequently appeared as guest on the highly-rated program

Question: How many years did late night run?
Self-contained rewrite: How many years did Late Night with David Letterman run?