You also have to keep in mind how old the character is. For example, if the story takes place in 1941 and the character is 20 years old, you should be looking at popularity charts from 1921.
My PNL is now rateable! (Top 25 for each gender):
http://www.behindthename.com/pnl/52996/85726Top rated:
Henry; Bottom rated:
Gerald