Thirty-five years ago, there were 65% fewer cars on the road as today. Riding road bikes, even in a small Southwest Georgia town, never felt particularly dangerous. Even riding directly through town on the most well-traveled routes was a daily occurrence, as I commuted from my parents' suburban home to the bike shop in the old part of downtown Albany. The rural roads and neighborhoods were easy; we even hosted winter training races, north of town, with 30 or so riders on open roads.
I don't need to say how...but all that changed with the availability of vehicle financing and the invention of cell phones.
Undoubtedly the risk was always there, but my awareness of it changed. The numbers definitely changed. I didn't know people who were killed by cars, back then. Now, I know several. I know many more who have been hit, most during hit-and-run incidents.