Sports utility vehicles have become the favourite family car in New Zealand, according to the local Transport Agency.

Almost one in three new-car purchases in 2011 was an SUV, giving them the largest segment of the market, Fairfax Group website reported.

The growth in SUV sales has come at the expense of big family cars which, in less than a decade, have gone from being the largest segment of the market to the smallest.

Transport Agency marketing manager Ian Stronach told the website the findings were intriguing given that fuel costs and environmental issues were rising.

People were choosing SUVs for safety and lifestyle reasons: "It's a perception, or self-image ... people like to see themselves in a sportier mode.

"SUVs are the balance between urban chic and rugged individualism. They are the new family transport."

Fairfax group motoring editor Dave Moore said developments in fuel efficiency meant many SUVs now had a smaller carbon footprint than many large cars.

"These days it's possible to buy an [SUV] which has a superior fuel economy and smaller carbon footprint than even a family sedan or hatchback."

Environment minister Nick Smith said an SUV with seven people in it was more efficient than a small car with a single occupant.

"It's pleasing the SUV market is quite focused on fuel efficiency and has improved considerably over the last five years," he said.

But Green Party transport spokeswoman Julie Anne Genter said people often felt they were getting a better deal when buying an SUV instead of a car, but in the long term the benefits waned with higher running costs.

Consumers needed to be aware of fuel economy.

Although SUVs made up the biggest segment of the market, no individual SUV featured in the top five best-selling models last year, with the Toyota Corolla the most popular, ahead of the Suzuki Swift.

In 2011, 29% of sales were SUVs, up from 26% in 2010, while large cars like the Holden Commodore and Ford Falcon made up just 9% of sales.

Stronach said the trend toward SUVs was an international one throughout developed countries.

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