[win311fwg]

Not quite. The value of the currency has declined by 33% since 1999.

Prices are subject to the combination of the value of the currency and the value of the good. Food may be worth more than in the past, for example, so you cannot look at the value of the currency alone.

[twoodfin]

The value of the currency relative to an evolving bag of reference goods.

[win311fwg]

Value is always relative. Typically currency is what we use as the relative point of comparison, but obviously you cannot compare the value of the currency with the value of the currency. Hence why we flip things around. A bag of goods, as opposed to a single item, filters out the noise of each individual good changing in value independently.

[Dylan16807]

Food is one of the things that's going to have the least change in value.

[win311fwg]

Quite the opposite. Value is essentially a function of scarcity relative to desire. Food desire may be, for all intents and purposes, stable, but availability is most certainly not. Something like a major weather event wiping out a crop can quickly change the scarcity profile. Food is especially prone to value variances over time.

[notahacker]

Also, desire for restaurant service is driven by people with disposable income looking to treat themselves much more than baseline food prices. Restaurants serving this demand can optimise prices for their limited capacity, and have staff and real estate costs to consider

[Dylan16807]

What specific definition of value are you using here? Sometimes terms with value get into the same realm as price, but the default definition of value is the benefit you're getting, and going to similar restaurants ten years apart is damn near the same benefit. Scarcity doesn't come into play.

[win311fwg]

Given that we're specifically talking about value in the context of currency and how that pertains to CPI, I am not sure where "benefit you're getting" would apply. CPI is definitely not interested in "the benefit you got".

However, if we are to change gears, the benefit you get out of a restaurant isn't constant either. Aside from maybe those trying to serve the elderly population, where there seems to be a viable niche of providing "remembrance of how things were in the good old days", restaurants that try to offer constant value quickly go out of business. They are forever needing to up their game to appeal to the typical clientele. Customers want increasingly more benefit as time marches forward to justify the visit.

An individual's perception of benefit is personal, so it is true that any given individual may not find increased benefit in restaurants trying to outdo each other by offering more and more benefits, but within populations it seems quite apparent that restaurants that "win" generally are offering more benefits (higher quality/more exotic/creative food, increasingly sophisticated ambiance, etc.) than they did in the past.

[Dylan16807]

> Given that we're specifically talking about value in the context of currency and how that pertains to CPI, I am not sure where "benefit you're getting" would apply. CPI is definitely not interested in "the benefit you got".

...yes it is? It's seeing how many dollars you need for some specific goods.

> the benefit you get out of a restaurant isn't constant either

It's not exactly constant but it's pretty close. Especially over a single decade. And we can assume here that people are going to similar restaurants.

[win311fwg]

No...? Price is what we use to "see how many dollars you need for some specific good".

To be sure, the P in CPI stands for price, but that doesn't mean it is the same thing as price. The C and I are also there to indicate that it is something else.

[asdff]

Pick your favorite crop and look at yields per acre over the last century.

[Dylan16807]

If I have to look at an entire century I think that proves my point.

[asdff]

I mean looking at fold change, even full order of magnitude increases is pretty interesting.