14M Americans live in extremely poor neighborhoods

Nearly 14 million Americans are living in extremely poor neighborhoods, more than twice as many as in 2000, a new report has found.

Brookings Institution's Metropolitan Policy Program tied growing poverty levels to the availability of affordable housing. It also said causes can include middle income families moving away or working class neighborhoodssliding into poverty if the local economy goes south and residents lose jobs.

In 2000, there were roughly 2,000 Census tracts where at least 40 percent of the residents were poor. In the period between 2010 and 2014, that number grew to nearly 4,200.

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