In the decade between the last two U.S. Census releases, each of New Jersey’s 21 counties became a little more diverse, according to one metric.
As part of the once-a-decade national head count taken by the Census, one data point released is called the diversity index. This number measures the probability that two random people in a given area will be of different racial and ethnic backgrounds.
For example, Hudson County’s diversity index for 2020 is 72. That means, for a given pair of people in Hudson County, there is a 72% chance they will be of different backgrounds. While that matches the highest mark of any county in the state, the demographics there are relatively stable compared with the ranking of 70 the county had in 2010.
In 2010, Warren had a diversity index of 26, making it one of five least diverse counties in the state. In the last decade, Warren County’s diversity index has added 13 points, the biggest jump in the state. It remains in the state’s bottom five in terms of diversity, but that’s only because the state as a whole is getting more diverse.
Statewide, New Jersey has a diversity index of 66, the 7th highest in the country. That’s up from 59 — and 10th place — in 2010.