CPI fails to factor in the changes of short term consumer trends...
say for example an increase in the consumption of cheaper substitute goods in the face of growing inflation, or the reduction of certain goods in the basket used in the cpi calculation..
Of course this is entirely delusionary. Consumers respond to increases in prices in goods they want by substituting ones that they want less.
If you go from steak at $20/lb to catfood at $1/lb---is that "deflation"?
Bet the wonks would imagine so.
Similarly like how there are changes downward in the CPI because of large, narrow changes in technology prices.
"Gee, I can get 5 gigahertz and 500 gigs versus 1 Ghz and 100 gigs just a few years ago for the same price."
They then pencil in a huge deflation in the price of the tech goods---even though the price of the 'Standard computer" needed to run most software (or the ones you can buy conveniently) has bottomed out quite well.
Getting way more gigs on your iPod doesn't make up for paying more on gasoline, insurance, housing and health care which are exploding.
All things you need and wish you really didn't.
Another statistical adjustment. Your health plan keeps on going up and up through the roof. Your employer pays out more and more and so do you. Guess what: the part of that the employer pays (often more than 50%) gets counted at
additional income in the statistics and not as inflation! (Even though the reality is that you keep on having to pay more and more to get a health plan of any given quality).
Whenever there's an arbitrary judgement call they usually go to the one that makes the lowest inflation number and the highest income number, regardless of actual human experience.