In a statement, a Statistics New Zealand (Stats NZ) spokesperson said the nationwide prosecution process is still under way with 15 convictions, nine cases that have been withdrawn and 36 cases that are yet to be completed.
"While it is a legal requirement to take part in the census, it's not practical to prosecute everyone who hasn't taken part," the spokesperson said.
"Cases have been prioritised based on a number of criteria, including whether there was an active refusal to take part in the census or a strong negative or abusive attitude displayed towards census staff.