<P> Mexico City is home to some of the best private hospitals in the country; Hospital Ángeles, Hospital ABC and Médica Sur to name a few . The national public healthcare institution for private - sector employees, IMSS, has its largest facilities in Mexico City--including the National Medical Center and the La Raza Medical Center--and has an annual budget of over 6 billion pesos . The IMSS and other public health institutions, including the ISSSTE (Public Sector Employees' Social Security Institute) and the National Health Ministry (SSA) maintain large specialty facilities in the city . These include the National Institutes of Cardiology, Nutrition, Psychiatry, Oncology, Pediatrics, Rehabilitation, among others . </P> <P> The World Bank has sponsored a project to curb air pollution through public transport improvements and the Mexican government has started shutting down polluting factories . They have phased out diesel buses and mandated new emission controls on new cars; since 1993 all new cars must be fitted with a catalytic converter, which reduces the emissions released . Trucks must use only liquefied petroleum gas (LPG). Also construction of an underground rail system was begun in 1968 in order to help curb air pollution problems and alleviate traffic congestion . Today it has over 201 km (125 mi) of track and carries over 5 million people every day . Fees are kept low to encourage use of the system and during rush hours the crush is so great, that authorities have reserved a special carriage specifically for women . Due to these initiatives and others, the air quality in Mexico City has begun to improve, with the air becoming cleaner since 1991, when the air quality was declared to be a public health risk for 355 days of the year . </P> <P> Mexico City is one of the most important economic hubs in Latin America . The city proper produces 15.8% of the country's gross domestic product . According to a study conducted by PwC, Mexico City had a GDP of $390 billion, ranking it as the eighth richest city in the world and the richest in Latin America . Mexico City alone would rank as the 30th largest economy in the world . Mexico City is the greatest contributor to the country's industrial GDP (15.8%) and also the greatest contributor to the country's GDP in the service sector (25.3%). Due to the limited non-urbanized space at the south--most of which is protected through environmental laws--the contribution of Mexico City in agriculture is the smallest of all federal entities in the country . Mexico City has one of the world's fastest - growing economies and its GDP is set to double by 2020 . </P> <P> In 2002, Mexico City had a Human Development Index score of 0.915, identical to that of South Korea . </P>

The greatest industrial center in latin america is located in this city
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