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. 2011 Mar 29;119(7):997–1002. doi: 10.1289/ehp.1002981

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(A) Median annual EC trends across select job categories. (B) EC trends across select job categories by census region. The boxes indicate 25th, 50th (median), and 75th percentiles. Extreme outliers are excluded for display purposes, and the length of the whiskers are bounded from above by 1.5 times the interquartile range.