New Zealand police have the identities of more than 7 million people in their systems.
They are adding to the cache at up to 250,000 identities a year.
The latest police report on the quality of their data discloses the figures, but previous similar reports do not have any to make a comparison by.
"The amount of personal identity data reflects demand on police services," principal assurance advisor Andrea Johnston said in a statement to RNZ.
The National Intelligence Application (NIA) "only holds personal identity data of people police have had cause to create a record about... such as offenders, victims of crime, people involved in a serious vehicle crash or missing people", she said.
The database also included people who were dead, did not live in New Zealand and duplicates.
"Almost 6 million are labelled as 'police identities' (created by police) and of those about a half are labelled as 'confirmed identities'," the 2022 report said.
Johnston said a 'confirmed identity' was not reflective of the accuracy of the personal identity data, but instead referred to an identity that has been tagged as 'confirmed'.
"That does not mean untagged identities are unconfirmed or inaccurate."
New additions can number as few as the 150,000 added in 2021 - 10,000 of them were "exact match duplicates - or up to 250,000.
Police were fixing up about 25,000 duplicates a year.