Consumer Price Index The CPI is the most widely used measure of inflation. In $1970,$ the CPI was $37.8,$ and in $2000,$ the CPI was $168.8 .$ This means that an urban consumer who paid $\$ 37.80$ for a market basket of consumer goods and services in 1970 would have needed $\$ 168.80$ for similar goods and services in $2000 .$ Find a simple exponential function of the form $y=a b^{\prime}$ that models the CPI for $1970-2000,$ and predict its value for 2010