Let's face it- most dating "rules" of the preceding decades have gone out the window. They're about as current as leisure suits and 8-tracks. Some rules simply faded away, while others rode the coattails of broader societal changes over time. One such rule was that men were to date women (somewhat) younger than themselves, and women were to date men (somewhat) older than themselves. This probably had to do with women wanting to date men who were mature and financially stable, while men sought women who were unquestionably fertile.