This dataset contains the true centroid point layer for the annually released statistical area 2 (SA2) boundaries as at 1 January 2020. The "true" centroid is the centre of mass of that polygon, such that if some flat substance of uniform thickness and density were cut into the shape of that polygon, then that object would balance at the centroid. The centroid is a useful way of summarizing the location of a set of polygons as points, particularly when used for comparative analysis. Note that the centroid could potentially fall outside the SA2 polygon, depending on the shape of the polygon. The dataset contains the EASTING and NORTHING attributes of the centroid point in NZGD2000 New Zealand Transverse Mercator (EPSG:2193) and LATITUDE and LONGITUDE of the centroid point in decimal degrees in WGS1984 (EPSG:4326) projection.
