The number of registered **cars **in the US increased by about 231.76% from 1950 to 1990, calculated by finding the difference between the two given values, then dividing this by the initial value and multiplying by 100 to get the answer as a percentage . ;
The percent increase in registered cars in the United States from 1950 to 1990 was approximately 231.76%. This was calculated by determining the increase in the number of cars and then dividing by the original amount from 1950. Finally, the result was converted to a percentage by multiplying by 100.
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