Calculating an 'apples with apples' figure for residential rates is difficult because councils use various mixes of rates, levies, and user charges. Our approach is based on work by Napier City Council to find an average residential rate. We sent an official information request to all councils requesting average residential rates using the formula below: 

Average residential rates = (X+Y)/Z 

X is the total of all rates (general and targeted) charged by the Council to residential properties; 

Y is the total amount of user charges or levies applicable to residential properties (for example, charges relating to metered water, infrastructure contributions, refuse collection, fire protection etc). This excludes Council charges that are not part of the rates demand (for example retail sales of Council rubbish bags). 

Z is the number of residential properties (however defined by the Council) within the Council's district or city. Councils were asked to use the closest definition (such as urban) should they have no classification for residential properties. 

While we think this approach is useful and fair, the average residential rates figure should be a guide only. Unitary authorities (Auckland Council, Nelson City Council, Gisborne, Tasman, and Marlborough District Councils and the Chatham Islands Council) can be expected to have higher rates than other territorial authorities because they perform and pay for the functions of a regional council. 

Average non-residential rates are calculated using the equivalent methodology for residential rates, but for charges and levies applicable to non-residential properties.