While there was a considerable upfront investment -equivalent to some USD 200 million in setting up the system, and some USD 300 million in buses, other transit options, and park-and-ride facilities - operating costs have proved to represent some 25% of annual revenues, rendering the investment cost-effective. Moreover, other benefits have been estimated on an annualised basis at some USD 85 million deriving from shorter travel times, USD 18 million from enhanced road safety, and USD 13 million from health and environmental benefits. Moreover, no effect was observed on the level of retail sales.