In 2004, women's life expectancy exceeded men's life expectancy by 5.2 years, the smallest gender gap in life expectancy since 1946. Life expectancy for whites was five years greater than that of blacks. Life expectancy for black and white men and women was as follows: 1  Black male: 69.8 years.  White male: 75.7 years.
But, that's not always the case. Safe following distances vary according to traffic speed and weather conditions and according to the type of vehicle you're driving. In good conditions, you should allow 2 seconds between your car and the vehicle in front of you. Here's an easy way to work that out.
Therefore, because you cannot see as far ahead at night, you need to slow down to give yourself more distance to stop your vehicle. The minimum stopping distance for a vehicle with normal brakes traveling 55 m.p.h. under favorable road and weather conditions is approximately 230 feet.