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Perry Mason on CBS peaked just after '60. It ran from 1957 to 1966 and was a top-20 show pretty much the whole time. In 1961-62 it reached number 5 on the charts. "The triumph of Perry Mason," wrote Thomas Leitch, "is a triumph of formula."
1960 was the year in which TV Westerns started to fall. They had become so prominent and so much a part of TV culture that it must have been hard to believe at first that this was really happening. But it had been a brief run, really. There were sixteen Westerns in 1957-58, 24 in '58-'59, a peak of 28 in 1959-60. Then 22 in 1960-61. Ten had been in the top 30 in 1957-58, only 8 in the top 30 in 1960-61.
The Untouchables first aired on October 15, 1959. The Twilight Zone ran from October 2, 1959 to September 18, 1964. The Andy Griffith Show debuted in our year, on October 3, 1960 (it ran until halfway through 1968, which is simply hard for me to fathom).
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Meantime, while the father's social mobility declines in importance, on January 21, 1960, the day after JFK was sworn in (new era!), Playhouse 90 was forced to cut back from weekly to twice monthly.
On election day, November 8, 1960, there were 90 million TV sets in the U.S., nearly one for every two Americans. The Kennedy-Nixon debates were watched by 66.5 million viewers! They were the first such debates of this sort (aired on TV but--more--really made for TV) and they remain to this day the highest-rated presidential debates ever. The last debate earned a 66 rating. Note too that the viewership went up from the first to the third debate, as word got out about how exciting and important they were - not down as is usually the case. (In RatingsWorld this effect is something like what you see for the seventh game of a World Series, like Red Sox-Reds in '75. As the quality of contest itself became clear, excitement grew.)
Newton Minow (I still can't get over that name) didn't just say that TV was "a vast wasteland" when he spoken at the National Association of Broadcasters convention in Washington on May 9, 1961. Here is a little more context. He told industry executives to "sit down in front of your television set when your station goes on the air and stay there without a book, magazine, newspaper, profit-and-loss sheet or rating book to distract you--and keep your eyes glued to that set until the station signs off. I can assure you that you will observe a vast wasteland." As Gary Edgerton in The Columbia HIstory of American Television unironically observes: "[T]he association's membership had never before heard anyone make a literary allusion to T. S. Eliot when discussing television."