Since the average new car in 2005 worldwide had a fuel economy level of about 817100km (29.4 miles per gallon), this means cars would have to reach 4L/100km (58.8 miles per gallon) by 2030. This will be very challenging, requiring an improvement of nearly a 3% per year in new-car fuel economy, on average, in every country. They include engine efficiency technologies, lightweight materials, improved body aerodynamics and improved vehicle components such as air-conditioning and low-rolling-resistance tyres.