Personally, I don't think monetary inflation is a reasonable metric at all. It's a second-order effect which has been given more importance than it deserves. Price inflation tells us much more about the actual state of the economy than the total number of dollars, which is almost completely arbitrary, given the amount of credit, fractional reserves, derivatives, quantitative easing, etc.

Well, I'm in complete disagreement. Mathematically speaking price deflation is just a weighted sum of individual prices. Well, one can include all prices if weights are equal to zero for most of them. And the problem?

The weighting is completely arbitrary, that's the problem. The can be lots and lots of

*price inflations* depending on distribution on weights, but somehow one of them is picked and called

*The Inflation*. (Of course, there already are inflation and core inflation)

Say what you want about the old definition of inflation, but it wasn't arbitrary.

The important thing to pay attention to is the price of basic goods and commodities.

Yes, but, I'd rather have supply and demand take care of it not the Central Banks, thank you very much. Also there are more than just monetary reasons why the prices of basics can go up/down. Bad/good weather, technological progress/regress, resource availability, new goods, shifts in preferences. Choosing price deflation as The Measure you just choose to ignore all those factors.