Answer
$33.08$%
Work Step by Step
The height of the point above 2008 is 8700. That is 8700 thousand = 8.7 million of motor vehicles were produced in the U.S. in 2008.
From (b): 13.0 million motor vehicles were produced in the U.S. in 1999.
The percent decrease in the number of motor vehicles: $\frac{13.0-8.7}{13.0}=0.3308=33.08$%
