The July 2008 issue of Hemmings Motor News included a feature story on the 1957 Cadillac Eldorado Brougham. When sold as a new car in 1957, the price was $13,074. It depreciated in value over the next few years. Then, in 1967, something interesting began to happen as seen in this table of values.
YearValue
1967 .................................$ 2,500
1977 .................................$ 5,500
1987 .................................$18,500
1997 .................................$25,000
2007 .................................$95,000
a. Construct a scatterplot for the data. Let 1967 be year 1, 1977 be year 11, 1987 be year 21, and so on. What do you notice about the trend?
b. Find an exponential regression equation that models this situation. Round the numbers to the nearest hundredth.
c. What kind of a rate has been used? What is the value of that rate to the nearest tenth of a percent?