Americans love to drive. More than 75 percent of adults carry a driver’s license, including 40 million who are 65 and older. But driving is more than just a passion or a pastime: It’s a lifeline. Studies show that giving up driving increases a person’s mortality risk and makes seniors more likely to land in nursing homes and suffer from depression. Yet the average American man outlives his ability to drive by six years; the average American woman, by 10 years.