I'd say years between sentient armor and extremis/CW (about three years, maybe?), and three-to-four months between Extremis & Civil War.

The usual rule of thumb with Marvel is that four years real time = one year of comics time, so Tony became Iron Man 10-12 years ago in comics time (as opposed to 45 years ago), did the serious alcoholism thing about 6-7 years ago, and got the Extremis just under a year ago current canon (2005 to 2008 being 3 years).