NOTE: June-14 is the first wave to combine the Mana and Internet votes, previous waves are Mana only figures.
The poll has a maximum margin of error of plus or minus 3.1 per cent.
Party Vote percentages are only based on eligible and decided voters. Respondents who are undecided, do not intend to vote or are ineligible to do so are excluded from the Party Vote.
The market research agency Ipsos interviews at least 1,000 New Zealand residents who are eligible to vote. Interviews are conducted over the telephone using CATI (Computer Assisted Telephone Interviewing). We conduct the poll over several days including a weekend to allow as many people equal chance of being interviewed. We select households randomly and call into urban and rural regions using quotas determined by age, gender and ethnicity. Interviewers ask to speak to the person in the household who is aged 18 years or over and is the next to have their birthday. If the person is not immediately available we call back repeatedly giving them every chance of participating. The Stuff.co.nz / Ipsos poll was conducted in accordance with the New Zealand Political Polling Code.
At the end of the survey we examine our data and apply weights to remove any biases that might occur. For example we find we have too many or too few of a particular quota. Weighting the data ensures the final sample looks as close as possible to the actual population. Our poll provides a maximum sampling error of +/-3.1%-point, at the 95% confidence level. This means we can be 95% confident that the survey results are within 3.1% of the result had we surveyed the entire population of the NZ population, when the analysis is based on all respondents surveyed.