Average Income: New Jersey had a population of 8.88 million people in 2019, with a median age of 40.2 and an average household income of $85,751. Between 2018 and 2019, New Jersey’s population fell from 8.91M to 8.88M, a 0.296 percent decrease, while its median household income increased from $81,740 to $85,751, a 4.91 percent increase.