This is the definitive set of area unit boundaries for 2013 as defined by Statistics New Zealand as at 1 January 2013.
Area units are aggregations of adjacent meshblocks with coterminous boundaries to form a single unbroken surface area (land and/or water). Exceptions to this rule are some area units comprising collections of geographically related inlets and marinas.
In an urban location, an area unit is often a collection of city blocks, while in rural situations area units may be equated to localities or communities. Area units must either define or aggregate to define urban areas, rural centres, statistical areas, territorial authorities, and regional councils.
Each area unit must be a single geographic entity with a unique name. The area unit pattern is revised once every five years in the year immediately before a Census of Population and Dwellings. There may also be changes in other years, in conjunction with local body boundary changes. Statistics New Zealand maintains a concordance file to ensure boundaries relating to earlier area unit patterns can also be generated.