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.
Keep a minimum of a good five car length from the car in front of you. You never know what other drivers are going to do or what could happen to you! If that feels too close or too far a rule of thumb is 1 second of following distance per 10 mph (16 km/h). That holds true especially in bad weather.