If you accidentally killed someone, how severely should you be punished?

Without getting too specific, let’s just say that you were doing something that millions of people do everyday, most of the time without mishap, but because you weren’t really thinking, or because you zoned out for a second, you caused an accident. The accident could just as easily have been a near miss or resulted in your own death. Unfortunately, as bad luck would have it, the other person died and the professionals who analyse these things, determined it was your fault.