Unlawfully obtaining or possessing regulated weapons or explosives in New Zealand

Offence: refers to any act or omission by a person/organisation or persons/organisations for which a penalty could be imposed by the New Zealand legal system. Offences in this collection are defined by the 2011 edition of the Australian and New Zealand Standard Offence Classification (ANZSOC).
Offender: refers to a person or organisation Police apprehend because Police allege the person or organisation is involved in a criminal incident involving one or more offences.
Proceeding: refers to a legal action initiated against an alleged offender for an offence(s). Police proceedings represent a count for each separate occasion on which police initiate a legal action against an offender. Each proceeding is classified to a principal offence and principal method of proceeding. It does not represent a count of offences.
Proceeding population: the measure involving counting a person once on each day they are proceeded against by police in the reference period, whether by court or non-court action.

http://www.police.govt.nz/about-us/publication/recorded-crime-victims-and-offenders-statistics-rcvs-and-rcos

Caution should be observed when making inferences about long-term trends in crime, particularly for types of offences that are known to be significantly under-reported (e.g. Sexual offences and minor offences not warranting insurance claims or medical treatment).

• substantive offences (e.g. robbery, breach of protection order);
• attempted offences (e.g. attempted robbery).
• aid and abet offences;
• conspiracy offences.

The offenders include both people and organisations (for which age and sex are flagged ad 'Not applicable')

• offences that Police are able to deal with by issuing an infringement notice
• offences that come under the authority of agencies other than NZ Police, such as Customs, Worksafe New Zealand, Inland Revenue, ACC, Ministry for Primary Industries, etc.

Increases in numbers of proceedings in June 2016 should be interpreted with caution. Some Police Districts (most notably Eastern, Counties Manukau and Waikato) undertook exercises to ensure records were up-to-date ahead of fiscal year end. Most formal actions against offenders were already up-to-date, so the updates primarily affected informal warning for adult offenders and other non-court actions for youth offenders.

At URL provided, select Offender Demographics (Proceedings) > Table 5.
Clear filter from Method of proceeding subdivision and Person/Organisation on the top-right corner. Use the time slider to select desired time period, then right click anywhere on the data and select 'Export Sex Age Boundary'.
Figure.NZ collated the whole time series by performing the steps above as many times as necessary. We created pivot tables in Excel to be able to process aggregated figures.

This dataset presents descriptive information about offenders in New Zealand. It also gives an overview of trends in proceedings against offenders.

The RCOS collection counts all alleged offenders recorded by NZ Police as prescribed in the NZ Police National Recording Standard (NRS), who have been proceeded against by police during the reference period.