Around 64 percent of people who live in urban slums are in Asia, as the region experienced rapid rural-to-urban migration that has left millions of urban dwellers in poverty, according to the World Bank. Lack of access to public transportation, jobs and affordable housing are among the many factors contributing to poverty, the report pointed out. Without supervision, the "modernizing" of urban areas can worsen the livelihoods of the urban poor. The report pointed to the example of bans on transport options such as trishaws and rickshaws in Asia. In some areas of China and Indonesia, such bans to eradicate congestion led to income losses and deprived the urban poor of affordable travel options.