Question: Does Upheaval Happen More at the End of Decades?

In 2008, Obama won on a campaign of change, which McCain imitated.  Clinton won in 1992 on a much more centrist message.

The world’s most famous stock market crash occurred in 1929.  The recession of the early 1980s arguably began with the 1979 energy crisis.  Likewise, the 2001 recession arguably began with the skyrocketing NASDAQ (dot-com) speculation in 1999.  The savings & loan crisis reached its peak in the late 1980s.  The worst economic crisis since the Great Depression began in 2007.

1968 may have been America’s politically most tumultuous year in the second half of the 20th century.  Also musically.  Elvis Presley made his big breakthrough in 1956.  Punk rock exploded in the late 1970s.  Apparently the first rap hit single came out in 1979.