When the insurance industry was starting out, it grouped everyone together, calculated the likely pay-out on claims and divided that amount among the group members as the premium. This was a simple, straightforward system for spreading the risk. If the insurers made good guesses, they ended up with a profit. If they had “bad luck”, they ended up with big losses. Because those in business prefer profits, the calculation of risk has become increasingly scientific. Actuaries collect detailed factual information about everyday events from traffic accidents to thefts to lightning strikes. There are statistics on all the risks covered by insurance companies. Now, these companies group people together on the basis of mathematical models of probability. Groups of safe drivers pay lower premiums. Because women are way safer drivers than men, groups of women drivers pay the lowest premiums.