A reader who saw my posting about www.wordcount.org, also suggests http://babynamewizard.com/namevoyager/lnv0105.html (Thanks Carol!) She calls it the coolest website ever and God's gift to fiction writers. She's right.
The site is the creation of Laura Wattenberg who labels it the "guide to every aspect of baby name style." You plug in a name and up pops a graph that displays the waxing and waning of the popularity of the name. My first stop was the obvious. JILL was #109 in popularity in the 1950s when my mother chose it. MARY dropped from #1 in 1890 to #63 in 2004. SUSAN graphs out like a witch's hat. From hardly there in the 1890s to a rapid rise to #4 in the 1950s and then a plunge. That's proof that every other girl in my high school class was named Susan.
Type in MEREDITH and you can see it shift from blue (a boy's name) to pink (the #153 in popularity in girl name in the 1980s).
Wattenberg (Laura -- #21 in 1880s; #16 in the 1960s; #129 in 2004) also has a blog that examines names as cultural indicators. Her latest posting analyzes name popularity according to red-blue states. For example, you'd be more likely to meet little Hannahs, Annas and Abigails populating the pre-schools in red states; at the birthday parties in coastal urban centers, guests would be Ashley, Sarah and Caroline.
As Laura explains, the strength of tradition seems to be biggest theme. Red staters are more prone to neologize--to create new names from surnames (Tanner), place names (Brooklyn), or simply appealing sounds (Kaden). Blue staters are more likely to stick to traditional naming stock. "In other words, the political conservatives turn out to be the naming activists, and the political progressives are the naming conservatives."
So, if you're naming a baby -- or a character in a novel -- make sure to check it out here first.