It's out with the old, and in with a whole new way of recording crime.

Police are moving to a new monthly count of victims and offenders, instead of individual offences.

The new system will be unveiled this morning and will see two records released for each policing district, every month.

One will count the age, gender and ethnicity of each person or business location victimised by certain kinds of crimes.

The other count will include data about the people accused of committing any criminal offence.

A victim will only be counted once, no matter how many times an offence is committed against them, reflecting more persistent crimes like family violence.

Some crimes, like drug offences and death threats, wouldn't have a victim counted at all.

Both offenders and victims will be categorised as Maori, European, Pacific, Asian or people who "look Indian".

However, people will be able to self-identify their gender or ethnicity to police officers.

Police hope the new count will reflect the actual harm of crime, including persistent family violence.

A spokesperson says they are already more focused on reducing the number of victimisations, rather than reducing the number of reported crimes.

Reported crimes can often reflect how willing people are to notify police about incidents, rather than the actual number of incidents going on.

The change of reporting system means the days of crime rates and resolution rates will soon be gone for good.

Police will stop their count of individual offences early in the new year, making it almost impossible to make accurate crime rate comparisons.