This is a really strange (i.e. wrong) comment considering that the CPI adjusts for changes in the size of things.

The response is not to the CPI - it is to an individual tracking food costs themselves anecdotally.

CPI tries to take into account changes in quality and quantity.

If new iPhone has better quality than old iPhone so that price increase of CPI is not the difference of iPhone prices. You are paying more to get more.

What metrics would you use to determine if an iPhone is better quality than older models?

Quality sounds rather subjective and they did not always calculate CPI with taking that into account. Seems like they don't share the criteria they use to determine 'quality'.

They added the quality weight to make the overall numbers look lower. I have zero idea if that distorts it, or makes it more correct.

For something like an iPhone you can just use the price that consumers are willing to pay to determine if it's better than older models. When a new model is introduced the retailers still have the old model in stock and continue selling it. If consumers are willing to pay more for the new model then it has higher value to them.

Here's a detailed example (with math!) of the CPI Hedonic Quality Adjustment for TVs.

I found it by googling "CPI quality adjustment".

https://www.bls.gov/cpi/quality-adjustment/questions-and-ans...

"Hedonic regression model" sounds fancy and all, but look at their charts just filled with arbitrary numbers accessing various features. Funny to see how they weighted various, now failed, technologies/features.

They share the information and document it. Please don't succumb to some conspiratory thinking.

They can't take everything into account and hedonic adjustments is used for only small percentage of products. That's one reason why it overestimates inflation.

I don't think the folks that make the CPI are part of some vast conspiracy. I just question their methods. Like all numbers from the government, politics are involved.

You can believe they are (slightly) wrong and not be a "conspiracy theorist/thinker" at the same time.

>Like all numbers from the government, politics are involved.

Not really. Details of how CPI is calculated has never been political issue.

Based on OP's detailed-orientedness, I'd assume he was tracking his total monthly food expenses.

I am indeed referring to total monthly food expenses, and also individual prices for things I track the unit cost of, like meat, dairy, and produce.

To break it down further, best unit prices from 2006 to present:

Lean ground beef: $3/lb -> $4/lb

Chicken breast: $26/4kg -> $26/4kg

Pork tenderloins: $2/lb -> $2/lb

Milk: $4/gal -> $4.50/gal

Apples: $0.69/lb -> $0.99/lb

Green Peppers: $0.99/lb -> $1.49/lb

I'll stop there but you get the idea. I've noticed pasta boxes shrinking from 500g to 454g at some point in the last 10 years, as did bacon going from 454g to 375g. But those are fairly isolated changes and bacon prices have also tripled in that time period for some reason.

Where are you in that mixes lb and kg like that?

I've never seen a 500g box of pasta in my entire life.

I've can't remember when apples were cheap, even the cheapest varieties.

Milk is priced by subsidied and loss leaders, so it isn't practical for tracking inflation.

I understand that, but if a container of food shrinks by an ounce or two over time most won't buy an entire extra one to make up the difference.

If you could buy all food by weight this would be easier to notice and make an apples to apples comparison. Hat's off to the parent comment if they even tracked it down to the exact amount of food and kept it consistent for years.

Most people set a budget of $X dollars of food that is rather generous and if they get slightly less food they don't notice because they are already buying an excess of calories most of the time.

As I mentioned in the sister comment I do indeed track unit prices for things like meat, dairy, and produce.

My total monthly expenses have increased by roughly 50-100% since 2006, but that's also because I now earn more, buy more expensive things like steak and good cheese, and am more physically active so eat larger quantities.

I actually think that I overstated food price increase marginally. Many things I buy are the same price they were 15 years ago.

I admire the thoroughness of your data collection. I don't doubt your numbers at all.

If anything the only huge inflation I ever see is not in consumer goods, but in appreciating assets.

Are you seriously suggesting that food prices have increased more and people are just generally eating less calories?

Allow me clarify, I think people in general consume more calories than they did in the past. They are just 'wasting' less food.

Most people when buying food budget money, not calories. So if food producers shave off a few ounces over time you won't notice because you already buy a surplus of food to begin with. The surplus just shrinks ever so slightly on the consumers end. That unused 2 ounces at the bottom of the mayo jar is now 1. That pack of fruit snacks has 1 less in the pouch, etc.

It usually takes a dramatic sudden change for most consumers to notice "shrinkflation".

I have noticed that when somebody says "so you are saying/suggesting X," X was never actually said/suggested. A frustrating thing to encounter in a discussion. Sorry if I was unclear.