A planet without automobiles
Cars have been around for 100 years. Annual car fatalities have been around 40,000 since at least as far back as 1960. If we extrapolate back to 1905 then upwards of 4 million people have died in car accidents in the United States, and an additional 3.2 million were never born. Therefore, it is conceivable that if not for car accidents the United States today would have 7.2 million more people living in it. Not enough to rival India or China, but still alot more.