20th+

In economics, inflation refers to a general progressive increase in prices of goods and services in an economy. When the general price level rises, each unit of currency buys fewer goods and services; consequently, inflation corresponds to a reduction in the purchasing power of money. The opposite of inflation is deflation, a sustained decrease in the general price level of goods and services. The common measure of inflation is the inflation rate, the annualised percentage change in a general price index.

Prices will not all increase at the same rates. Attaching a representative value to a set of prices is an instance of the index number problem. The consumer price index is often used for this purpose; the employment cost index is used for wages in America. Differential movement between consumer prices and wages constitutes a change in the standard of living.

The causes of inflation have been much discussed (see below), the consensus being that growth in the money supply is typically the dominant causal factor.[6]

If money was perfectly neutral, inflation would have no effect on the real economy; but perfect neutrality is not generally considered believable. Effects on the real economy are severely disruptive in the cases of very high inflation and hyperinflation. More moderate inflation affects economies in both positive and negative ways.

The negative effects include an increase in the opportunity cost of holding money, uncertainty over future inflation which may discourage investment and savings, and if inflation were rapid enough, shortages of goods as consumers begin hoarding out of concern that prices will increase in the future.
Positive effects include reducing unemployment due to nominal wage rigidity, allowing the central bank greater freedom in carrying out monetary policy, encouraging loans and investment instead of money hoarding, and avoiding the inefficiencies associated with deflation.

Keynesian economics proposes that changes in the money supply do not directly affect prices in the short run, and that visible inflation is the result of demand pressures in the economy expressing themselves in prices.

There are three major sources of inflation, as part of what Robert J. Gordon calls the "triangle model":

Demand-pull inflation is caused by increases in aggregate demand due to increased private and government spending, etc. Demand inflation encourages economic growth since the excess demand and favourable market conditions will stimulate investment and expansion.
Cost-push inflation, also called "supply shock inflation," is caused by a drop in aggregate supply (potential output). This may be due to natural disasters, or increased prices of inputs. For example, a sudden decrease in the supply of oil, leading to increased oil prices, can cause cost-push inflation. Producers for whom oil is a part of their costs could then pass this on to consumers in the form of increased prices. Another example stems from unexpectedly high insured losses, either legitimate (catastrophes) or fraudulent (which might be particularly prevalent in times of recession). High inflation can prompt employees to demand rapid wage increases, to keep up with consumer prices. In the cost-push theory of inflation, rising wages in turn can help fuel inflation. In the case of collective bargaining, wage growth will be set as a function of inflationary expectations, which will be higher when inflation is high. This can cause a wage spiral. In a sense, inflation begets further inflationary expectations, which beget further inflation.
Built-in inflation is induced by adaptive expectations, and is often linked to the "price/wage spiral". It involves workers trying to keep their wages up with prices (above the rate of inflation), and firms passing these higher labor costs on to their customers as higher prices, leading to a feedback loop. Built-in inflation reflects events in the past, and so might be seen as hangover inflation.

Demand-pull theory states that inflation accelerates when aggregate demand increases beyond the ability of the economy to produce (its potential output). Hence, any factor that increases aggregate demand can cause inflation. However, in the long run, aggregate demand can be held above productive capacity only by increasing the quantity of money in circulation faster than the real growth rate of the economy. Another (although much less common) cause can be a rapid decline in the demand for money, as happened in Europe during the Black Death, or in the Japanese occupied territories just before the defeat of Japan in 1945.

The effect of money on inflation is most obvious when governments finance spending in a crisis, such as a civil war, by printing money excessively. This sometimes leads to hyperinflation, a condition where prices can double in a month or even daily. The money supply is also thought to play a major role in determining moderate levels of inflation, although there are differences of opinion on how important it is. For example, monetarist economists believe that the link is very strong; Keynesian economists, by contrast, typically emphasize the role of aggregate demand in the economy rather than the money supply in determining inflation. That is, for Keynesians, the money supply is only one determinant of aggregate demand.

Some Keynesian economists also disagree with the notion that central banks fully control the money supply, arguing that central banks have little control, since the money supply adapts to the demand for bank credit issued by commercial banks. This is known as the theory of endogenous money, and has been advocated strongly by post-Keynesians as far back as the 1960s. This position is not universally accepted – banks create money by making loans, but the aggregate volume of these loans diminishes as real interest rates increase. Thus, central banks can influence the money supply by making money cheaper or more expensive, thus increasing or decreasing its production.

A fundamental concept in inflation analysis is the relationship between inflation and unemployment, called the Phillips curve. This model suggests that there is a trade-off between price stability and employment. Therefore, some level of inflation could be considered desirable to minimize unemployment. The Phillips curve model described the U.S. experience well in the 1960s but failed to describe the stagflation experienced in the 1970s. Thus, modern macroeconomics describes inflation using a Phillips curve that is able to shift due to such matters as supply shocks and structural inflation. The former refers to such events like the 1973 oil crisis, while the latter refers to the price/wage spiral and inflationary expectations implying that inflation is the new normal. Thus, the Phillips curve represents only the demand-pull component of the triangle model.

Another concept of note is the potential output (sometimes called the "natural gross domestic product"), a level of GDP, where the economy is at its optimal level of production given institutional and natural constraints. (This level of output corresponds to the Non-Accelerating Inflation Rate of Unemployment, NAIRU, or the "natural" rate of unemployment or the full-employment unemployment rate.) If GDP exceeds its potential (and unemployment is below the NAIRU), the theory says that inflation will accelerate as suppliers increase their prices and built-in inflation worsens. If GDP falls below its potential level (and unemployment is above the NAIRU), inflation will decelerate as suppliers attempt to fill excess capacity, cutting prices and undermining built-in inflation.

However, one problem with this theory for policy-making purposes is that the exact level of potential output (and of the NAIRU) is generally unknown and tends to change over time. Inflation also seems to act in an asymmetric way, rising more quickly than it falls. It can change because of policy: for example, high unemployment under British Prime Minister Margaret Thatcher might have led to a rise in the NAIRU (and a fall in potential) because many of the unemployed found themselves as structurally unemployed, unable to find jobs that fit their skills. A rise in structural unemployment implies that a smaller percentage of the labor force can find jobs at the NAIRU, where the economy avoids crossing the threshold into the realm of accelerating inflation.

Other economic concepts related to inflation include: deflation – a fall in the general price level; disinflation – a decrease in the rate of inflation; hyperinflation – an out-of-control inflationary spiral; stagflation – a combination of inflation, slow economic growth and high unemployment; reflation – an attempt to raise the general level of prices to counteract deflationary pressures; and asset price inflation – a general rise in the prices of financial assets without a corresponding increase in the prices of goods or services; agflation – an advanced increase in the price for food and industrial agricultural crops when compared with the general rise in prices.

Today, most economists favour a low and steady rate of inflation. Low (as opposed to zero or negative) inflation reduces the severity of economic recessions by enabling the labor market to adjust more quickly in a downturn, and reduces the risk that a liquidity trap prevents monetary policy from stabilising the economy. The task of keeping the rate of inflation low and stable is usually given to monetary authorities. Generally, these monetary authorities are the central banks that control monetary policy through the setting of interest rates, by carrying out open market operations and (more rarely) changing commercial bank reserve requirements.

Tuesday, April 17, 2012

Liquidity Trap

22-10-15 Japan - national debt, liquidity trap vs artificial inflation - VisEco > .

Debt ..

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Deflation ..

24-3-22 Things I (Do) Worry About: Deflation || Peter Zeihan > .

A liquidity trap is a situation, described in Keynesian economics, in which, "after the rate of interest has fallen to a certain level, liquidity preference may become virtually absolute in the sense that almost everyone prefers holding cash rather than holding a debt (financial instrument) which yields so low a rate of interest."

A liquidity trap is caused when people hoard cash because they expect an adverse event such as deflation, insufficient aggregate demand, or war. Among the characteristics of a liquidity trap are interest rates that are close to zero and changes in the money supply that fail to translate into changes in the price level.

Liquidity trap conditions:

Interest rates are very low, and consumers nevertheless prefer to save rather than spend or invest in higher-yielding bonds or other investments.
Consumers choose to hoard cash instead of choosing higher-yielding investments because of a negative economic outlook.
Not limited to bonds, a liquidity trap also affects other areas of the economy = as consumers spend less, which can mean businesses are less likely to hire.
A liquidity trap mutes monetary policy efforts to stimulate growth because interest rates are already at or close to zero, thus perpetuating recession.
Escaping a liquidity trap? Raising interest rates; self-regulation as prices fall to attractive levels; increased government spending.

Speculative bubble .
Subprime mortgage crisis .
Too big to fail .
Zero interest rate policy .
Inverted yield curve .