The Taylor Rule is a specific policy rule for fixing interest rates proposed by the Stanford University economist John Taylor. The rule is a formula for setting interest rates depending on changes in the inflation rate and economic growth.

A simplified formula is: r = p + 0.5y + 0.5 (p – 2) + 2

r = the short term interest rate in percentage terms per annum.

p = the rate of inflation over the previous four quarters.

y = the difference between real GDP from potential output.

This assumes that target inflation is 2% and equilibrium real interest rate is 2%

Taylor argued that when:

- Real Gross Domestic Product (GDP) = Potential Gross Domestic Product
- Inflation = its target rate of 2%,
- Federal Funds Rate (FFR) should be 4% (that is a 2% real interest rate).

If the real GDP rises 1% above potential GDP, then the FFR should be raised by 0.5%.

If inflation rises 1% above its target rate of 2%, then the FFR should be raised by 1.5%.

He stated that the real interest rates should be 1.5 times the inflation rate.

This rule has been suggested as one that could be adopted by other central banks – ECB, Bank of England, etc for setting official cash rates. However, the rule does embody an arbitrary 2% inflation target rather than, say 3% or 4%, and it may need to be amended to embody alternative inflation targets at different times or by different central banks. The advantages of having such as explicit interest rate rule is that its very transparency can create better conditions for business decisions and can help shape business people’s and consumers’ expectations. Central banks prefer to maintain an air of intelligent discretion over the conduct of their policies than to follow rules, but to some extent they do unwittingly follow a Taylor rule. This makes the rule a useful benchmark against which actual policies can be judged.

**New Zealand and the Taylor rule**

When the Taylor Rule is applied to the New Zealand economy it suggests an optimal, OCR of more than 8% – see graphic from live gross domestic product (GDP) tracker. A rate as high as this would do significant damage to the economy even if inflation did get down to the 2% target for inflation. Households and businesses would find it particularly hard with incomes being squeezed. An OCR of this level would have an unwieldly impact on households and businesses, squeezing incomes.

**Criticisms of Taylor rule**

The theory assumes that only the central bank can affect the equilibrium real rate of interest and there is a closed economy with households that have identical consumption patterns and the same declining marginal utility. However, an economy is a much more intricate machine which aims to allocate scarce resources to satisfy the utility of economic agents such as individuals, firms and government. The dominant model for many years has been “Dynamic Stochastic General Equilibrium” (DSGE) and it takes all the characteristics of an individual (this person is typically called the representative agent) which is then cloned and taken to represent the typical person in an economy. These agents make supposedly perfect decisions by optimising, working out the kinds of mathematical problems in an instant. This almost rules out any fluctuations in the natural rate that might arise from alterations in how individuals discount the future, from how consumption preferences may differ among individuals or alter over time for one individual, or from differences in the distribution of wealth.