Have vehicles gotten more fuel-efficient over the years? between 1960 and 1999 the size and shape of automobiles in the united states has changed almost annually. the amount of fuel consumed by these vehicles has also changed. the following table describes the average fuel consumption per year per passenger car in gallons of gasoline.

This is correct. The changes in shapes imply changes in aerodynamics which means that the car takes less effort to move. This in turn means that it spends less gasoline. Also, the quality of the gasoline is higher due to increased number of octanes which also means that fuel is consumed less. Many other factors are included, but the final answer is: Yes, they have.

2xy/9 is the answer to this problem