The Figures column brings you the numbers we didn't know a week ago. This week: numbers from the International Engine of the Year, rallies from 1960 and 2011, and Saab's surprising sales success.

CO2 emissions of just 92g/km make the Fiat 500 with Duologic transmission and the award-winning TwinAir engine the greenest petrol car available - if you define 'greenness' purely in terms of CO2 emissions.

With120bhp/litre the upcoming performance version of Fiat's TwinAir engine has almost the same specific output as Ferrari's 4.5-litre 458 Italia V8 (125bhp/litre).

Crews drove 3300 miles on the gruelling Liège-Rome-Liège rally. By contrast the next round of the 2011 World Rally Championship, the Argentina Rally is just 905 miles, and that's one of the longer events. 'The Liège' was won outright in 1960 by Pat Moss and her navigator, Ann Wisdom: Stuart Turner's book Harnessing Horsepower - The Pat Moss-Carlsson Story was released this week.

At 47 million joules per kilogram, the energy content of petrol is about ten times that of TNT. And less than half that of hydrogen.

732,853,855 miles were driven by all the cars which took part in the last Which? motoring survey.

170,000 vehicles were made last year at Suzuki's European plant in Hungary.

Up to 1860 litres of luggage can be accommodated in Vauxhall's new Zafira Tourer, announced this week.

Bonhams has sold £27million-worth of Aston Martins since 2000 at its annual sales at Aston Martin Works Service in Newport Pagnell. The next one is this Saturday.

Saab sales are up 77.7% year on year, in a market that is down 8.5 per cent year on year overall.

A 6874 mile (11,063km) journey begins on Sunday when Nicky West and Rob Stacey will set off from Hatfield House, destination Egypt and the Pyramids - in a 1967 Mini Minor. The trip is in aid of the Willow Foundation.