Dairy cattle in New Zealand farms

http://datainfoplus.stats.govt.nz/Item/nz.govt.stats/6362a469-f374-412e-ac25-d76fd0962003#/nz.govt.stats/6362a469-f374-412e-ac25-d76fd0962003/190

For the 2002 Agricultural Production Census, Statistics NZ sourced the population from the Business Business Register and the Inland Revenue Client Register. These sources were checked against industry lists and AgriBase to ensure all large units were included in the population.
After the 2002 Census, Statistics NZ used the Business Register for the census and survey populations.

Over the years, Stats NZ have changed the core information gathered in agricultural production collections.
Since 2002, these collections have gathered information on livestock and arable farming, horticulture, and forestry with the following exception:
In 2004, 2006, 2008, 2010, 2013, 2015, 2016 the surveys collected information on livestock and arable farming, and forestry (with no horticulture production information).

At URL provided, select 'Industry sectors > Agriculture > Variable by Total New Zealand (Annual-Jun)'

The Agricultural Production Survey is part of an ongoing programme of agricultural production statistics conducted in partnership with the Ministry for Primary Industries. Previous sample surveys were held in 2003–06, 2008–11, and 2013–14, with censuses in 2002, 2007, 2012, and 2017.

To collect information about livestock farming (including sheep, beef and dairy cattle, and deer), crop growing (including grain and seed crops), fruit, vegetables, wine grapes, forestry and farm practices (including fertiliser use).