Conversation so far:
When did Walter Cronkite  join CBS Evening news?
On April 16, 1962, Walter Cronkite succeeded Douglas Edwards as anchorman of the CBS's nightly feature newscast.
for how long was Walter Cronkite the anchor of CBS evening News?
Walter Cronkite served as anchorman for the CBS Evening News for 19 years.
What kind of stories did Walter Cronkite report?
Walter Cronkite reported many events from 1937 to 1981, including the assassinations of President John F. Kennedy, civil rights pioneer Martin Luther King Jr., and Beatles musician John Lennon.
What was Walter Cronkite known as during his time at CBS evening news?
Walter Cronkite was often cited as the most trusted man in America after being so named in an opinion poll.

Question: What were his ratings for the Apollo 11 and Apollo 13 missions?
Self-contained rewrite: What were Walter Cronkite ratings for the Apollo 11 and Apollo 13 missions in the CBS Evening news?