What is inflation really, or what's the use of gold?

Those who have read this previous post probably (and understandably) wonder how reasonable the Alternative CPI measure is. After all, it seems to indicate that our cost of living has increased almost four-fold since 1993, which seems rather steep (mostly since for only very few of us has our income increased four-fold in the same period). There is no question that the official numbers are seriously gamed (see this note, or this), but that, in and of itself mean that the alternative numbers are right. My personal view is that the Alternative CPI measure is more a measure of inflation (that is, the debasement of the dollar) than the actual CPI growth -- the latter tends to be smaller than the former, since the money-printing is offset by technological progress, which causes computers to drop from $6000 in 1981 to$150 at Walmart in 2011 (the latter computer also being several orders more powerful), and your car's fuel consumption to go from 8mpg in the 1960s to 40mpg today.

A good proxy for inflation is, however, provided by prices of commodities (still not perfect, since exploration and mining also have made considerable strides), and since a representative basket of commodities is rather cumbersome to hold, a good proxy for one is gold -- indeed, gold is almost miraculously convenient -- it is compact, it does not degrade, and it saves you from buying shares of oil tankers parked off Singapore.

The above seems counterintuitive (after all, we have all heard of the gold bubble, but [relatively]  few of us have heard of the the wool, rice, natural gas, or any one of the many other possible commodities bubbles. Well, luckily for us, the IMF maintains a commodities price index, so we can compare and contrast. Here is the requisite chart:

Some explanation might be in orer: The very smooth red line shows how many dollars you would have were you to invest $1 in a money market account in January of 1993. The almost-as-smooth green line shows how many of those dollars you would need according to the Alternative CPI computation to purchase a basket of goods worth$1 in Jan 1993. The jagged purple line shows how many of those dollars you would need to purchase however much gold you could buy for a dollar in January of 1993, while the really jagged light blue line shows the same for a dollars worth of a commodity basket. The conclusions, at least to me, are:

• The Alternative CPI seems, as advertised, to be a good measure of inflation (and is, therefore, a bit of an overestimate of the actual price inflation).
• There is no gold bubble (a conclusion also drawn in a previous post from other data).
• Gold (in addition to its compactness) is a better gauge of monetary inflation than the commodities basket (witness the huge volatility in the latter starting in late 2007  or, for that matter, just in this May.
• The red line (your risk free return) was added just to make the chart more depressing. Unfortunately, it has achieved its goal brilliantly.