What are the characteristics strengths of Comsumer Price Index?

Question

If the CPI is imperfect, why do we use it?

Answer 1

Nothing invented by humanity is perfect so of course the CPI is imperfect.  There is not a perfect correlation between the CPI and the other aspects of the economy that are of interest.  There are a number of other metrics that in certain areas have stronger correlations with certain other metrics.

CPI has been calculated for a long time and therefore there is a long history of CPI and other economic metrics.