Supporting information:

Series description - Economic indicators

Consumers price index (CPI)

Statistics New Zealand All Groups CPI. Base: June 2006 = 1000. From September 1999 the index excludes interest charges and section prices. Source: Statistics New Zealand.

CPI target measure

Underlying inflation until the September 1997 quarter, CPIX inflation through to the June 1999 quarter, then CPI inflation from the September 1999 quarter. CPI Inflation has been adjusted by Statistics New Zealand to exclude interest and section prices from the September 1999 quarter to the June 2000 quarter.

Tradables inflation

This series is calculated by Statistics New Zealand and comprises all those goods and services in the CPI that are imported or that are in competition with foreign goods either in domestic or foreign markets. Data prior to June 1999 has been backcast by RBNZ.

Non-tradables inflation

This series is created by Statistics New Zealand and comprises all those goods and services in the CPI that do not face foreign competition, e.g. government charges. Excludes interest rates.

Data prior to June 1999 has been backcast by RBNZ.

CPI inflation less housing non-tradable items

This series is created by the Reserve Bank and excludes from the CPI non-tradable housing related CPI items (including rates and insurance).

Non-tradable inflation less housing items

This series is created by the Reserve Bank and excludes from non-tradable inflation housing related items (including rates and insurance).

Petrol prices

The petrol price component of the CPI.

Trimmed mean inflation

From March 2001 quarterly percentage changes, and from December 2001 annual percentage change trimmed mean figures are those published by Statistics New Zealand. Note that the figures quoted prior to those dates are RBNZ estimates. Users should note that the SNZ estimates may differ slightly from those previously calculated and published by the Reserve Bank due to some differences in methodology. Additional data and technical notes are available on Statistics New Zealand's website.

Trimmed mean inflation is the weighted mean inflation rate after trimming 5 per cent from each end of the distribution of price changes in the individual components of the CPI, when the price changes are ranked from lowest to highest.

Quarterly and annual trimmed means

SNZ’s quarterly trimmed mean inflation rate is calculated from the distribution of quarter-to-quarter inflation rates in the CPI items. In contrast, the annual trimmed mean inflation rate is calculated from the distribution of item level annual price changes (the change from one quarter in a given year to the same quarter of the following year).

Because the annual and quarterly trimmed means presented here are calculated from distributions of price changes that are calculated over different intervals (one quarterly, the other annual), the annual measure cannot simply be inferred from the quarterly measure. That is, the annual trimmed mean here is not equal to the quarterly trimmed mean inflation rate, compounded over 4 quarters. The annual trimmed mean comes directly from the behaviour of the annual inflation rates in the CPI items over time. In contrast, the quarterly trimmed mean comes from the behaviour of the quarterly inflation rates in the CPI’s components over time.

Exponentially smoothed measure

This series is created by the Reserve Bank. It is a weighted mean of the lagged values of quarterly CPI inflation, with the most recent outturn having the highest weight. For more technical information see Holden, R (2006) “Measuring Core Inflation”, Reserve Bank of New Zealand Bulletin, December (vol 69, no 4).

Factor model

This series is created by the Reserve Bank. It is a dynamic factor model that estimates the common component of inflation from all the CPI classes for which we have data going back to the beginning of 1992. Ninety six of the 105 classes currently in the CPI are included. For more technical information see Giannone, D and T Matheson (2006) “A New Core Inflation Measure for New Zealand”, Reserve Bank of New Zealand Discussion Paper 2006/10.

Weighted median inflation

From March 2001 quarterly percentage changes, and from December 2001 annual percentage change weighted median figures are those published by Statistics New Zealand. Note that the figures quoted prior to those dates are RBNZ estimates. Users should note that the SNZ estimates may differ slightly from those previously calculated and published by the Reserve Bank due to some differences in methodology. Additional data and technical notes are available on Statistics New Zealand's website.

Weighted median inflation is the 50th percentile by weight of the distribution of price changes in the individual components of the CPI, when the price changes are ranked from lowest to highest. In other words, the weighted median inflation rate is the inflation rate for the item or group of items that is in the middle of the total distribution. In any period, then, half of the components of the CPI regimen (by their weight in the regimen) exhibit lower inflation rates than the weighted median, and the other half show higher inflation rates. Thus the weighted median places zero weight on prices that change by relatively large and relatively small amounts in a given period. Put more technically, the weighted median inflation rate is the inflation rate associated with the weighted 50th percentile of the ranked distribution of price changes in a given period.

Quarterly and annual weighted medians

SNZ’s quarterly weighted median inflation rate is calculated from the distribution of quarter-to-quarter inflation rates in the CPI items. In contrast, the annual weighted median inflation rate is calculated from the distribution of item level annual price changes (the change from one quarter in a given year to the same quarter of the following year).

Because the annual and quarterly weighted medians presented here are calculated from distributions of price changes that are calculated over different intervals (one quarterly, the other annual), the annual measure cannot simply be inferred from the quarterly measure. That is, the annual weighted median here is not equal to the quarterly weighted median inflation rate, compounded over 4 quarters. The annual weighted median comes directly from the behaviour of the annual inflation rates in the CPI items over time. In contrast, the quarterly weighted median comes from the behaviour of the quarterly inflation rates in the CPI’s components over time.

CPI less food, petrol & Government charges

This series is created by the Reserve Bank. It is Statistics New Zealand All Groups CPI excluding the food group, petrol copmponent and central and local government charges. Central and local government charges currently includes items such as Housing NZ and local authority rentals, land transfer registration fee, local authority rates, water supply and part of refuse disposal, electricity, prescription charges and oral contraception, general practitioner fees, vehicle relicensing fees, road user charges, driver licensing fees, postage, state and integrated school donations and fees, university and polytechnic fees, and cheque duty.

CPI less energy and fuel

This series is created by the Reserve Bank. It is Statisitcs New Zealand All Groups CPI excluding the household energy subgroup and vehicle fuels.

GDP deflator

This implicit price deflator is derived from Statistics New Zealand's expenditure GDP data and is calculated by dividing real expenditure GDP by nominal expenditure GDP. Source: Statistics New Zealand

Retail turnover

Measures actual retail sales (excluding businesses with annual GST turnover of less than $30,000). Source: Retail Trade Survey - Statistics New Zealand.

Wholesale turnover

Measures actual wholesale sales. Source: Quarterly Wholesale Trade Survey - Statistics New Zealand (replaces the Economic Survey of Distribution).

Manufacturing turnover

Measures actual manufacturing sales and other income. The non-food series excludes the primary food processing industry group. Source: Economic Survey of Manufacturing – Statistics New Zealand.

Building permit issues

Number of building permits issued for new dwellings (houses and flats) and the dollar value of building permits issued for other new building activity. Excludes permits for alterations and additions to existing buildings. Quarterly data are sums of monthly data. Source: Statistics New Zealand.

Manufactured additions to fixed assets

The change in value of fixed assets in the manufacturing industry (eg, premises, machinery). Source: Economic Survey of Manufacturing - Statistics New Zealand.

Retail stocks

Records the value of stocks held in the retail sector. Source: Retail Trade Survey - Statistics New Zealand.

Wholesale stocks

Records the value of stocks held in the wholesale sector. Source: Wholesale Trade Survey - Statistics New Zealand.

Manufacturing stocks

Records the value of stocks held in the manufacturing sector. Source: Economic Survey of Manufacturing – Statistics New Zealand.

Labour cost index

An economy-wide index of salary and wage rates. Base: June quarter 2001 = 1000. Source: Statistics New Zealand.

Hourly earnings

Average hourly earnings (ordinary time and overtime). Source: Quarterly Employment Survey, Statistics New Zealand.

Producers price index

The inputs index measures the change in costs of production (excluding labour). The outputs index measures the change in prices received by producers. The outputs index is exclusive of GST and the inputs index excludes GST for most industry groups. Base (both indexes): December quarter 1997 = 1000. Source: Statistics New Zealand.

Registered unemployed

The number of people registered as unemployed with Work and Income New Zealand. Quarterly figures are averages of monthly figures. Source: Work and Income New Zealand.

Official unemployed

The number of people without a paid job who are available for work and who have actively sought work within the past four weeks. Source: Statistics New Zealand.

Filled jobs

Fulltime and part time employees plus working proprietors. Source: Quarterly Employment Survey, Statistics New Zealand.

Terms of trade

The terms of trade index measures the changing volume of imports that can be funded by a unit volume of exports. This will reflect exchange rate changes and shifting commodity prices. Base: Average for the ten years ended June 1989 = 1000. Source: Statistics New Zealand.

Imports of goods (fob)

The value of imports of goods to New Zealand, “free on board” (the value at the port of departure, excluding overseas freight and insurance costs). Source: Statistics New Zealand.

Exports of goods (fob)

The value of exports from New Zealand, “free on board” (the value at the port of departure, excluding overseas freight and insurance costs). Source: Statistics New Zealand.

Current account balance

The sum of the cross-border balances on merchandise trade, services trade, investment income and transfers.

Expenditure-based GDP

A measure of total final purchases in the economy. Includes stock-building. Real series is based in 1995/96 dollars. Source: Statistics New Zealand.

Real production-based GDP

A measure of total value-added in the economy in 1995/96 dollars. Source: Statistics New Zealand.

Nominal production-based GDP

Statistics New Zealand does not produce nominal production-based GDP data. The series used in the table is a Reserve Bank of New Zealand estimate.