In order to achieve trade benefits, however, the U.S. economy must reallocate production factors between sectors. Thus, free trade also leads to costs associated with workers displaced by import competition and offshore outsourcing. According to the Department of Labor (DOL), displaced workers are defined as "persons 20 years of age and older who lost or left jobs because their plant or company closed or moved, there was insufficient work for them to do, or their position or shift was abolished". The International Labour Organization (ILO) states that workers bore high adjustment costs such as unemployment, lower wage during transition, obsolescence of skills, training costs, and personal costs (e.g. mental suffering). These trade costs, albeit relatively smaller than the benefits, are highly concentrated by region, industry and worker demographics. For instance, some occupations, like teacher, have not experienced import competition while for shoe manufacturing occupations import competition has increased by 40 percentage points.