Fuel prices fell 3 cents per litre across the board on 19 January, reflecting modest reductions in the imported cost of crude oil and refined fuels during the week prior. Since then, global commodity prices have continued to decline slightly, but these reductions have been offset by a fall in the value of the NZ dollar, so the net effect is little change in the landed cost.

However, according to AA PetrolWatch's analysis, the imported cost of diesel has fallen more sharply than petrol and, despite the lower Kiwi$, the importer margin (retail price less costs) is at the top of the range. This means there is room for oil companies to pass these cost savings onto motorists in the form of a drop in the pump price - provided the exchange rate doesn't fall any further. No change in the price of petrol is anticipated, although the lower value of the NZ dollar does not bode well.

AA PetrolWatch notes that the differential between 91 and 95 octane petrol is now between 6-8 cents per litre depending on brand. Many motorists will be unaware of this, as service stations now tend to only advertise the price of 91 octane and diesel. Traditionally, the price gap was just 5 cents but it has been slowly rising due to increasing costs for premium fuel during much of this year (although lately the cost has fallen back). 98 octane petrol, where available, sells for 15c more than 91 octane.