Suppose that in 1990, the average plane ticket from New York to San Francisco was $240 but rose to a price of $430 by 2007. Determine the relative change in price from 1990 to 2007, and then refer to the chart to compare this change to the overall rate of inflation according to the CPI.

Average Annual Consumer Price Index
Year CPI Year CPI
1990 130.7 2000 172.2
1991 136.2 2001 177.1
1992 140.3 2002 179.9
1993 144.5 2003 184.0
1994 148.2 2004 188.9
1995 152.4 2005 195.3
1996 156.9 2006 201.6
1997 160.5 2007 207.3
1998 163.0 2008 215.3
1999 166.6

Question

Suppose that in 1990, the average plane ticket from New York to San Francisco was $240 but rose to a price of $430 by 2007.  Determine the relative change in price from 1990 to 2007, and then refer to the chart to compare this change to the overall rate of inflation according to the CPI.

Average Annual Consumer Price Index
Year	CPI		Year	CPI
1990	130.7		2000	172.2
1991	136.2		2001	177.1
1992	140.3		2002	179.9
1993	144.5		2003	184.0
1994	148.2		2004	188.9
1995	152.4		2005	195.3
1996	156.9		2006	201.6
1997	160.5		2007	207.3
1998	163.0		2008	215.3
1999	166.6

anonymous · Answer

relative change is| (x1 - x2) / ((x1+x2)/2)|. find the relative change of the value and compare it to the year's CPI change.