Northland Regional Council's spending on core services dropped from $26.7 million to $26.1 million, while its operating income rose from $29 million to $32.2 million.
Across the four councils, about $173.7 million of operating income was funded by rates in the year to June 2013.
Nationwide, local authorities' spending on core services fell from $8.5 billion to $8.3 billion. Operating income increased 1 per cent to $7.9 billion.
Statistics NZ local authorities statistics manager Michele Lloyd said income from rates increased $90 million in 2013, the lowest increase since the global financial crisis in 2009.
In the year ended June 2013, local authorities' operating deficit was $392 million, an improvement from the June 2012 year deficit.
Local Government New Zealand (LGNZ) president Lawrence Yule said the spending figures were skewed by Auckland and Christchurch data. He said he would not expect to see "massive changes" in provincial local authority spending.
LGNZ used the term "core services" to refer to roading and core infrastructure projects, while Statistics NZ used it to cover "pretty much everything that council does", he said.
"The key drivers [for the spending decrease] are actually in some of the major infrastructure project delays in Auckland and Christchurch.
"If you took them out and said 'well they're going to spend at the rate they were going to spend' then actually spending would go up. It's pretty much an Auckland and Christchurch story ... they're such big players that they make a big difference."
Probe into council still on-going
The Serious Fraud Office is continuing its investigation into the past affairs of the Far North District Council but is not releasing any specific details of the inquiry.
The SFO launched an investigation into the FNDC in July, after being called in by current Mayor John Carter following an internal investigation.
When the investigation was announced, former Far North mayor Wayne Brown said he was confident it would not turn up any evidence of impropriety against him. He said the secrecy surrounding the investigation cast aspersions on all council staff and contractors.
The SFO this week confirmed that the investigation related to the council is continuing. A spokeswoman said the SFO would be releasing nothing further on the investigation at this stage.
An internal investigation by the FNDC after Mr Carter was elected found matters of concern, but neither the SFO nor the council is commenting further on which aspects of the council's operations - or who - is being investigated.
Mr Carter said after July's announcement that the council was supporting the SFO investigation, which came about late last year after he and councillors commissioned an independent consultant to look into council activities.
The outcome of the investigation was referred to the SFO.
The SFO generally deals with cases that involve more than $2 million or if the matter is in the public interest.
