CBS Evening News a one-evening test broadcast on August 19, 1965, before permanently switching to the format on January 31, 1966. Cronkite's prime time special report, "Who, What, When, Where, Why", broadcast on February 27, 1968, ended with his declaration that the United States could only hope for a stalemate in Vietnam. It is often credited with influencing Lyndon Johnson's decision to drop out of the race for President. "If I've lost Walter Cronkite ... [I]'ve lost Middle America", he stated. Under Cronkite, the newscast began what would eventually become an 18-year period of dominating the ratings among the network evening news programs.
Walter Cronkite events that alter and illuminate our times ... and you were there." In 1971, the show was revived and redesigned to attract an audience of teenagers and young adults, hosted again by Cronkite on Saturday mornings. In 1957, he began hosting "The Twentieth Century" (eventually renamed "The 20th Century"), a documentary series about important historical events of the century composed almost exclusively of newsreel footage and interviews. A long-running hit, the show was again renamed as "The 21st Century" in 1967 with Cronkite hosting speculative reporting on the future for another three years. Cronkite also hosted "It's News to Me",