The problem is laymen care about cost of living, not CPI. But news agencies commonly talk about inflation with CPI rather than an actual cost of living. Which is what matters to people living ordinary lives.
Given this, the answers to your questions should be obvious. The answer, as far as laymen are concerned, is 3.5%. Improvements don't matter either. If we eliminated every car other than a Porsche, as far as laymen are concerned then car inflation went up by around 150%.
>Given this, the answers to your questions should be obvious.
If the answer seems obvious, then the question isn't fully understood, because there are trade-offs involved in CPI calculations.
There's no such thing as a "layman." Different people in different regions experience different CPI. Inflation for all goods in the Northeast might be 2.1% over the past ten years, but could be 1.6% in the South for the same basket. that might not sound like much, but that means that inflation is rising 25% faster in the Northeast.
No matter what you do, CPI at a national level won't accurately reflect any group. People in the South will claim it's way too high, and people in the NE will complain that it's way too low, etc, etc.
If you want real numbers, relevant to your situation, then the BLS provides the ability to calculate your own person CPI based on what you buy and where you live.
Given this, the answers to your questions should be obvious. The answer, as far as laymen are concerned, is 3.5%. Improvements don't matter either. If we eliminated every car other than a Porsche, as far as laymen are concerned then car inflation went up by around 150%.