Since the September statement annual inflation has fallen to 1 per cent, much lower than the 1.3 per cent the Reserve Bank had forecast. Globally inflation pressures are weak, reflecting excess capacity and falling oil prices.
On the export front, dairy prices at Fonterra's fortnightly auctions have fallen 53 per cent from their peak in April.
The September statement's forecasts built in a cumulative drop in export prices generally of 14.4 per cent between the March quarter this year and the March quarter next year, of which 6.6 per cent has eventuated so far, as recorded by Statistics New Zealand's overseas trade indices.
But those data come with a lag and so far reflect less than a third of the actual fall in dairy prices.
On the other side of the scales, the strength of net immigration flows has surprised the Reserve Bank, along with other forecasters.
Governor Graeme Wheeler cited it, and the associated risk of a resurgence in house price inflation, last month when announcing the bank would not be easing its loan-to-value ratio (LVR) restrictions on new residential mortgage lending.
Deutsche Bank chief economist Darren Gibbs said the Reserve Bank's September forecasts assumed the net flow of working age migrants would peak at 42,000 in calendar 2014, which he takes to be consistent with a total net inflow of about 45,000.
"On current trends a net inflow of at least 52,000 seems likely this year and it will take a significant change in trend for next year's assumption not to be exceeded by an even larger margin," Gibbs said.
And the most recent data suggest that the housing market in Auckland may be getting a second wind.
Auckland house prices rose a seasonally adjusted 1.6 per cent in the three months to July, on Quotable Value's data, but by November three-monthly growth had accelerated to 2.3 by per cent.
Barfoot and Thompson reported sales in the city climbed last month to their highest level since May, and the average price was 10.6 per cent up on November last year.
"It's becoming clearer that uncertainty ahead of the 20 September election had a dampening effect on activity - most prominently in the housing market, given that a broader capital gains tax on property was one of the most significant policies at stake in the election," Westpac economist Michael Gordon said.
"Since then, we've seen a strong rebound in property listings, mortgage approvals, house sales and building consents - though the last of those hasn't rebounded as much as we would have expected if pre-election nerves were the only thing going on."
ASB expects the next move in the OCR to be an increase in September and sees risks around that as balanced.
"Inflation could yet pick up materially for a variety of reasons," ASB economist Chris Tennent-Brown said. "But the longer the Reserve Bank remains on hold the greater will become the conviction that growth, migration and the housing market are past their peak, and the less likely future OCR increases would become."
Wheeler acknowledged last week that he can only influence short-term interest rates; long-term ones reflect conditions in global markets.
The Reserve Bank raised its OCR by 100 basis points between March and July, but longer-term mortgage rates had fallen as a result of a decline in long rates in the major economies.
Only 44 per cent of mortgage debt is at floating rates, down from 57 per cent a year ago.
