Here's a GIF of the most popular girls' names by state from 1960 to 2012. Watching the waves is somewhat hypnotizing. For me, I want to know why Jennifer ran from 1970 through 1984 for the total population and had all 50 states from 1973 through 1978, yet when 1985 rolls around Jessica is the total population winner and Jennifer carries a single state (IL). The only other name to carry all 50 states was Lisa in 1965.
When the change comes, it's immediate and pretty much nationwide. There's clearly a MA thesis in there somewhere and potentially a PhD dissertation (assuming it hasn't already been done).
http://i.imgur.com/qWL4Wl8.gif
Answered my own question. The tear-jerker movie Love Story came out in 1970 and Ali McGraw's lead character was named Jennifer. The roll of the tide is still interesting, though.
Who's got the explanation for Jessica in 1985?