Consumers Price Index: December 2014 quarter

Imputation Due to unavailability at the time of price collection, on average we impute 1–2 percent of prices(not including seasonal items such as winter clothing) each quarter. We often do this by carrying forward the previous quarter’s price. Other imputation we do is to apply the movements of similar categories of items.

For the December 2014 quarter, we also imputed quarterly price movements for prices collected directly from retail outlets for the following regional pricing centres:

• Whangarei – imputed from Hamilton
• Napier-Hastings – from Tauranga
• New Plymouth – from Hamilton
• Palmerston North – from Hamilton
• Nelson – from Dunedin
• Invercargill – from Dunedin.

We did not receive prices for the above pricing centres during the December 2014 quarter, due to industrial action by some price collectors.

The December quarter also includes monthly prices collected for food and some non-food items. On average, we impute 0.7 percent of prices (not including seasonal fresh fruit and vegetables) in a typical month. For the December 2014 quarter CPI, we imputed November monthly food price movements for the prices collected directly from retail outlets, for the following regional pricing centres:

• Whangarei – imputed from Hamilton
• Napier-Hastings – from Tauranga
• New Plymouth – from Hamilton
• Invercargill – from Dunedin.

Industrial action by some price collectors meant we didn't receive prices for the above pricing centres during November 2014.

We also imputed November and December food and non-food monthly price movements for the prices collected directly from retail outlets in Palmerston North from Hamilton.