KEY POINTS:
For all the hot air about curbing greenhouse gases, the burn-off of fossil fuels to move people and goods up and down the country's roads remains big business for the Government.
Last year, the Government raised more than $2.3 billion from taxes on petrol and diesel sales, and about $120 million in royalties on local oil and gas production.
It reaped just under $1.4 billion in petrol excise, and $922 million in GST on petrol and diesel, according to Automobile Association calculations from Government sales tables.
The Ministry of Economic Development also reports a healthy increase in royalties on locally-produced oil and gas, most of it exported, from $110 million in 2006-07 to almost $127 million this financial year.
There is no excise duty on diesel, and $852 million in road user charges paid separately by buyers of that fuel in calendar 2007 are excluded from the revenue calculation, as these are pumped straight back into the national land transport account.
But despite resentment among some motorists over the tax content of punishing petrol prices, that has declined proportionally with every upward lurch dictated by global extractors and traders of what is a dwindling energy resource.
Total taxes now stand at just under 74c a litre, or about 35 per cent of the retail price of 91-octane petrol compared with 66.4c a year ago, when they accounted for 42 per cent.
Duties and direct levies have remained at 50.539c on each litre of petrol sold since April last year, as the retail price for 91-octane has soared from 155.9c to 210.9c at most stations _ and to 212.9c at BP outlets.
The Government says it has been paying back more than the total value of those imposts _ apart from a 7.33c accident compensation levy (soon to be increased) and other items totalling less than 1c _ to the land transport account for roads and to a lesser extent for public transport.
A law change before Parliament is to confirm the Government commitment to the full "hypothecation" of petrol excise for land transport purposes, although other funding sources may yet be needed if fuel sales and hence tax revenues fall too far against even higher oil prices.
This financial year's land transport fund of $2459 million _ of which $259 million went to road policing _ drew $746 million from petrol excise, $818 million from road user charges, $219 million from motor registration fees and $657 million from direct Crown appropriations.
Although GST of 23.4c has increased in direct proportion to price rises, perceptions of massive long-term Government windfalls are not supported by the AA's annual figures, despite its call on Finance Minister Michael Cullen to ease motorists' pain by at least foregoing that portion which is heaped on fuel excise.
An increase of $31 million in GST on petrol last year was largely offset by a fall of $26.7 million in receipts from diesel sales. But diesel prices have soared this year at an even faster rate than petrol, and overall GST payments for the two fuels of $109 million in March were $20.1 million higher than for the same month of last year.
The Treasury says that, on the other hand, excise of $1316 million collected in the year to April on easing petrol sales was $70 million _ or 5 per cent _ lower than for the previous 12 months.
Although Dr Cullen argues that extra GST collected on petrol and diesel is balanced by revenue lost on other items which people can no longer afford, the changes may alter placements in a table ranking New Zealand fuel taxes at the low end of OECD rates. The most recent version of the table published on the Ministry of Economic Development's website, which ranks this country as enjoying the fifth-lowest petrol prices and taxes of 27 OECD countries, was for the three months to December.
Petrol prices have risen at least 40c since then and, although that is a symptom of a world-wide problem, the variability of GST may yet upset the country's future rankings.
