By the way, the speed of the buses depends on many factors. There are systems that are quite slow, with an average speed of 18 km/h, and fast ones like those in Johannesburg — those are about two times faster. Though the speed is not very impressive, one should note that it's the average speed — and it guarantees no traffic jams and delays. For instance, the average speed of public traffic in St. Petersburg is about 10 km/h. What is more, according to the data presented at one of the recent press conferences, the speed of public transport continues to decrease.