The Equity Index (EQI) Explained: What Replaced School Deciles in New Zealand

From 2023 the Ministry of Education replaced school deciles with the Equity Index (EQI). Both exist to direct extra funding to schools whose students face more socio-economic barriers, but they are built very differently, and the change matters when you read school rankings.

How deciles worked

Deciles put every school into one of ten groups based on the census characteristics of the neighbourhoods its students came from. Decile 1 schools drew from the most deprived areas and received the most equity funding; decile 10 the least. Because the groups were so coarse, two schools with almost identical communities could sit in different deciles, and the label became a shorthand for "good" and "bad" schools that it was never meant to be.

How the Equity Index works

The EQI is a single number for each school, currently ranging from about 344 (fewest barriers) to 569 (most barriers). It is calculated from anonymised administrative data about each student actually enrolled: parental education and income, benefit history, housing transience, parents' corrections history and similar factors, averaged across the school. A lower number means the school's students face fewer barriers to achievement.

Three things follow from this design:

• It is far more precise than a decile. There are hundreds of possible values instead of ten.
• It describes students, not teaching. A school with an EQI of 380 has a more advantaged intake than one with 500; nothing in the number says which school teaches better.
• It is recalculated regularly as the roll changes, so a school's number can move a few points each year without anything changing inside the school.

Reading EQI on this site

Every New Zealand school profile shows its EQI alongside its roll, growth and, for secondary schools, school-leaver NCEA attainment. The Success Index uses EQI as its largest component because, across thousands of schools, community advantage is the strongest single predictor of average attainment. That is exactly why you should read it carefully: a school that achieves high NCEA attainment with a high EQI is doing something remarkable, and a low-EQI school with middling attainment may be coasting.

Use the comparison tool to put a school's attainment next to schools with a similar EQI. That tells you more than the raw number ever will.

What EQI does not tell you

It says nothing about the quality of teaching, pastoral care, the arts or sport, whether the school suits your child, or how students progress during their time there. Treat it as context for everything else you learn on a visit.