100 people

If the entire population of the US was shrunk to only 100 people, keeping all of the ratios intact, then 1 person would be incredibly stupid and 1 would be insanely smart.

75 of the people would be bad drivers, 2 would be good drivers, 7 would be off the road due to an accident, 15 would be under age and only 1 would have been smart enough to voluntarily stay off the road. There would only be 3 parking spaces and the stupid person would always be in front of you.

97 people would have bad manners. The remaing 3 people would be the Queen of England, Miss Manners, and the incredibley smart person.

68 of the people would make up the statistics because the remaining 14 people would be bad at math.