Cultural landmarks tied to population marks [audio 2min]

A quick pop-culture survey of what was going on when the U.S. population hit 100 million in 1915 and 200 million in 1967: what people were reading, what they were listening to, what they were naming their babies, etc. We'll hear samples of what constituted a hit in those years, plus today's No. 1 single in the United States.