Chris McDowall has created an extraordinary interactive data-visualisation which shows the party vote results of every single one of the hundreds of voting places in the 2017 general election. He explains his work here – and explore it below.

Roughly every three years, New Zealand holds a general election. In the preceding weeks, a small army of volunteers and officials establish voting places up and down the country. Last Saturday, over 2500 sports clubs, halls, libraries, churches, hospitals and garages became official voting stations. I am fascinated by the geography of these places and over the last few elections I’ve made various maps of them.

Commentators typically discuss election results at the level of electorates. “Who won Northland? Did Labour underperform in New Lynn? What should we make of the swing left in the Nelson party vote?” These are important questions, yet I finding myself wondering other things. I want to peel back the familiar blue and red patchwork map and catch glimpses of what we collectively do in these public spaces.

How did folk vote at Kowhai Intermediate in Kingsland? (Apparently National’s party vote dropped from 35% to 29% while Labour climbed from 27% to 43%).

What about Albany Mall on the Shore? (Nearly 10,000 people made advance votes here: 7,000 to National, 2000 to Labour and the rest spread across the minor parties.)

Hmmm… what went down at Lake Tekapo School? (Just 176 voters, reduced from 243 in 2014. The party vote went strongly National, mirroring the 2014 results, sitting around 68%).

Fine resolution results data exists. The polling station names and counts are published on the NZ election results website. Yesterday I downloaded that data, folded it inside out, and turned it into an interactive map.

Circles are sized relative to the number of votes received. Blue dots are places where National got over 50% of the party vote. Red dots are where Labour exceeded 50%. Click any polling place to see further detail.

Explore the map for yourself. Pick a favourite city, or use one as a jumping off point to elsewhere.

These maps are subtle. Be careful how you read them. Avoid assumptions about relationships between a voting place location and its local residential neighbourhoods. Many people vote a considerable distance from their home or workplace. This is not to imply that there are not patterns in the data, more that any conclusions should be tentative. These maps offer clues into broad geographic patterns and detailed histories of specific stations.

Also note that each voting station serves multiple electorates, accepting votes from people on the general and Māori rolls. The Auckland Hospital voting place sits within Auckland Central and Tāmaki Makaurau, but it also serves the neighbouring general electorates Epsom and Maungakiekie.

Finally, the election results remain preliminary and these maps do not include the outstanding special votes. The maps also miss out some of the special teams that collect votes from retirement homes and prisons.

Also, why is nobody talking about the Chatham Islands swing towards Labour?