The pilot stated that he estimated the airplane's fuel supply during his preflight planning by calculating the fuel consumed during the two previous flights. The pilot departed for his destination and planned to land with 45 minutes of fuel reserve. During the flight, the airplane encountered wind stronger than forecast and the airplane consumed more fuel than he had estimated. On descent for landing, the airplane experienced a total loss of engine power and the pilot attempted to glide to the runway. As the airplane's airspeed and altitude decreased, the pilot opted to land on the freeway below. The airplane touched down in the middle lanes, skidded along the pavement, and came to rest in a ditch. During the accident sequence the airplane incurred damage to the right wing and horizontal stabilizer. Post-accident examination of the airplane by a Federal Aviation Administration inspector revealed that both tanks were absent of fuel and that there was no evidence of a preimpact mechanical anomaly.