Who can summarize this income inequality in the united states has reached its highest peak since the great depression (link is external). americans in the top 1 percent of earners currently make a staggering 40 times as much (link is external) as the bottom 90 percent. furthermore, in 1978 the top 0.1 percent of the population laid claim to 7 percent of the nation’s wealth. by 2012, that amount had increased to 22 percent (link is external). across industrialized nations, income inequality has been linked to an array of harmful outcomes, including higher rates of debt (link is external), crime (link is external), mental illness (link is external), and even mortality (link is external). to better understand such correlations, researchers are investigating how economic inequality might influence the behavior of those who are aware of it.