If the number of vehicles on Delhi roads continues to increase unabated, within two years they would be crawling at an average speed of 11 km per hour, a report said. The report by the Central Raod Research Institute (CRRI) found that if the traffic volume rises at the current rate, the average speed of vehicles in Delhi would be reduced to 11 km per hour by the year 2000. The average speed on the capital's roads in 1988 was 25 km per hour.