A 2005 study by the German Federal Interior Ministry (Bundesministerium des Innern) indicated that Autobahn sections with unrestricted speed have the same accident record as sections with speed limits. The only identifiable source of traffic risks in connection with speeding have been high-powered light trucks that came up within the last 15 years and as they are used by courier services (e.g. Mercedes-Benz Sprinter and trucks alike). Over the years they were only capable of speeds comparable to heavy duty trucks, but since manufacturers began to build in significantly more powerful engines they attain speeds of up to 180 km/h. This led to a significant portion of fatal accidents being caused by such vehicles  due to the driver overestimating their or the car's abilities to cope with sudden and heavy braking, side-winds, etc.