The different types of monetary policy undertaken by various nations can normally be categorized under one or more of the following approaches.

Inflation targeting
Under this policy approach the target is to keep inflation, under a particular definition such as Consumer Price Index, within a desired range.
The inflation target is achieved through periodic adjustments to the Central Bank interest rate target. The interest rate used is generally the interbank rate at which banks lend to each other overnight for cash flow purposes. Depending on the country this particular interest rate might be called the cash rate or something similar.
The interest rate target is maintained for a specific duration using open market operations. Typically the duration that the interest rate target is kept constant will vary between months and years. This interest rate target is usually reviewed on a monthly or quarterly basis by a policy committee.

Changes to the interest rate target are made in response to various market indicators in an attempt to forecast economic trends and in so doing keep the market on track towards achieving the defined inflation target. For example, one simple method of inflation targeting called the Taylor rule adjusts the interest rate in response to changes in the inflation rate and the output gap. The rule was proposed by John B. Taylor of Stanford University.

The inflation targeting approach to monetary policy approach was pioneered in New Zealand. It is currently used in Australia, Brazil, Canada, Chile, Colombia, the Czech Republic, Hungary, New Zealand, Norway, Iceland, India, Philippines,Poland, Sweden, South Africa, Turkey, and the United Kingdom.

Price level targeting
Price level targeting is similar to inflation targeting except that CPI growth in one year over or under the long term price level target is offset in subsequent years such that a targeted price-level is reached over time, e.g. five years, giving more certainty about future price increases to consumers. Under inflation targeting what happened in the immediate past years is not taken into account or adjusted for in the current and future years.

Monetary aggregates
In the 1980s, several countries used an approach based on a constant growth in the money supply. This approach was refined to include different classes of money and credit. In the USA this approach to monetary policy was discontinued with the selection of Alan Greenspan as Fed Chairman. This approach is also sometimes called monetarism. While most monetary policy focuses on a price signal of one form or another, this approach is focused on monetary quantities.

Fixed exchange rate
This policy is based on maintaining a fixed exchange rate with a foreign currency. There are varying degrees of fixed exchange rates, which can be ranked in relation to how rigid the fixed exchange rate is with the anchor nation. Under a system of fiat fixed rates, the local government or monetary authority declares a fixed exchange rate but does not actively buy or sell currency to maintain the rate. Instead, the rate is enforced by non-convertibility measures (e.g.capital controls, import/export licenses, etc.). In this case there is a black market exchange rate where the currency trades at its market/unofficial rate.

Under a system of fixed-convertibility, currency is bought and sold by the central bank or monetary authority on a daily basis to achieve the target exchange rate. This target rate may be a fixed level or a fixed band within which the exchange rate may fluctuate until the monetary authority intervenes to buy or sell as necessary to maintain the exchange rate within the band. (In this case, the fixed exchange rate with a fixed level can be seen as a special case of the fixed exchange rate with bands where the bands are set to zero.)

Under

a system of fixed exchange rates maintained by a currency board every unit of local currency must be backed by a unit of foreign currency (correcting for the exchange rate). This ensures that the local monetary base does not inflate without being backed by hard currency and eliminates any worries about a run on the local currency by those wishing to convert the local currency to the hard (anchor) currency.

Under dollarization, foreign currency (usually the US dollar, hence the term “dollarization”) is used freely as the medium of exchange either exclusively or in parallel with local currency. This outcome can come about because the local population has lost all faith in the local currency, or it may also be a policy of the government (usually to rein in inflation and import credible monetary policy).

These policies often abdicate monetary policy to the foreign monetary authority or government as monetary policy in the pegging nation must align with monetary policy in the anchor nation to maintain the exchange rate. The degree to which local monetary policy becomes dependent on the anchor nation depends on factors such as capital mobility, openness, credit channels and other economic factors.

Gold standard
The gold standard is a system under which the price of the national currency is measured in units of gold bars and is kept constant by the government's promise to buy or sell gold at a fixed price in terms of the base currency. The gold standard might be regarded as a special case of “fixed exchange rate” policy, or as a special type of commodity price level targeting.

The minimal gold standard would be a long-term commitment to tighten monetary policy enough to prevent the price of gold from permanently rising above parity. A full gold standard would be a commitment to sell unlimited amounts of gold at parity and maintain a reserve of gold sufficient to redeem the entire monetary base. Today this type of monetary policy is no longer used by any country, although the gold standard was widely used across the world between the mid-19th century through 1971. Its major advantages were simplicity and transparency. The gold standard was abandoned during the Great Depression, as countries sought to reinvigorate their economies by increasing their money supply. The Bretton Woods system, which was a modified gold standard, replaced it in the aftermath of World War II. However, this system too broke down during the Nixon shock of 1971.

The gold standard induces deflation, as the economy usually grows faster than the supply of gold. When an economy grows faster than its money supply, the same amount of money is used to execute a larger number of transactions. The only way to make this possible is to lower the nominal cost of each transaction, which means that prices of goods and services fall, and each unit of money increases in value. Absent precautionary measures, deflation would tend to increase the ratio of the real value of nominal debts to physical assets over time. For example, during deflation, nominal debt and the monthly nominal cost of a fixed-rate home mortgage stays the same, even while the dollar value of the house falls, and the value of the dollars required to pay the mortgage goes up. Mainstream economics considers such deflation to be a major disadvantage of the gold standard. Unsustainable (i.e. excessive) deflation can cause problems during recessions and financial crisis lengthening the amount of time an economy spends in recession. William Jennings Bryan rose to national prominence when he built his historic (though unsuccessful) 1896 presidential campaign around the argument that deflation caused by the gold standard made it harder for everyday citizens to start new businesses, expand their farms, or build new homes.

The American Monetary Association Team

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