In 2013, 43.9 per cent, or 158,042 crimes, were resolved.
The crimes with the lowest resolution rates were burglary, unlawful entry and breaking and entering.
While the number of these crimes remained fairly steady year-on-year -- 53,265 incidents were reported to police in 2014, or 1.9 per cent more than in 2013 -- fewer of these crimes were resolved.
Nationwide, 12.1 per cent of those crimes were resolved last year. Auckland had the lowest resolution rate in the country, at 6.1 per cent.
That compares with a 13.8 per cent national resolution rate in 2013, and a 7.6 per cent rate in Auckland.
Burglaries committed in Waitemata and Counties/Manukau Police Districts also had a resolution rate below 10 per cent. Waikato had a resolution rate of 11.2 per cent for burglaries.
Theft and related offences were the highest proportion of crimes last year, with 119,323 incidents reported to police -- 2.9 per cent less than in 2013, with population growth taken in to consideration.
Of those reported, 21.7 per cent were resolved, while in Auckland 12.7 per cent were resolved.
A spokeswoman for Police Minister Michael Woodhouse said police's Prevention First strategy had delivered a lower overall crime rate.
"While resolution rates have slightly decreased in 2014 from the previous year, the overall drop in crime rate shows the Government's strong focus on law and order is delivering great results and preventing more New Zealanders becoming victims of crime."
Total crimes
2014: 350,389
2013: 360,411
Auckland crime:
Offences reported in 2014: 42,297
Offences reported in 2013: 43,734
Offences resolved in 2014: 12,306
Offences resolved in 2013: 13,995
Burglary 2014:
Reported nationally: 53,265
Resolved nationally: 6464
Reported in Auckland: 7269
Resolved in Auckland: 447