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World population could peak lower, sooner 

Directed economic investment can improve economies through health and education access, say research authors.

A crowd of people cross the street in midtown Manhattan on October 31, 2011 in New York City. Around the world countries marked the global population reaching seven billion Monday. The UN is using Monday to symbolically mark the day as demographers are not sure exactly when the world's population will reach the seven billion mark.
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