The Mexico City Metrobús (former official name Sistema de Corredores de Transporte Público de Pasajeros del Distrito Federal), simply known as Metrobús, is a bus rapid transit (BRT) system that has served Mexico City since line 1 opened on 19 June 2005. As of February 2018, it consists of seven lines that cross the city and connects with other forms of transit, such as the Mexico City Metro. The most recent line to open was line 7, running for the first time double-decker buses along the city's iconic boulevard, Paseo de la Reforma. In 2016, Metrobús carried on average 1,152,603 passengers on weekdays. Impact Line 1 replaced 372 standard buses and microbuses that served Avenida de los Insurgentes with 212 articulated buses that run at an average speed of , doing as maximum. Doing so, travel times along the corridor were reduced up to 50%. Besides addressing the bus service problem, the BRT Metrobús project emerged in the context of the city's efforts to reduce air pollution with a program called Proaire 2002–2010. According to Metrobús, annual environmental benefits include a reduction of of carbon dioxide, of carbon monoxide, of NOx, and of PM10 particulates. Passenger access and payment Ticketing is by pre-paid proximity smartcard, which travellers have to pass through turnstiles at the entry to the separated bus platforms. During the early months of the system's operations, limited availability of the cards required a temporary method for access to the system involving purchasing a normal single-trip paper ticket at a cost of MXN$4.50. Starting in October 2005, and with smartcard supply able to cover the demand, access is done exclusively by using the card. As of 2022, the single-trip cost is MXN$6.00 (USD$). A new MB smartcard, preloaded with one voyage, can be purchased for MXN$15.00 and "recharged" for MXN$6.00 per trip. There is a supplemental fee of MXN$30.00 for trips to or from the airport. The smartcard system has generated controversy, especially from occasional and one-time users who complain about the MXN$15.00 fee for a single-voyage card, for this is common that sometimes people ask others who have the smartcard to charge for them a trip. Service is free for those over 70 years old, or disabled, as well as for children under 5 accompanied by an adult. Lines and hours Line 1 The line starts at Metro Indios Verdes, a large multimodal transport node in the Gustavo