##half of u. s. undergraduates. attendance at one of these institutions is associated with higher wages, even if a degree is not completed. evidence suggests that each year of credit at a community college is worth almost as much, in terms of increased earnings potential, as a year at a four - year college. the average student who entered, but did not complete, community college earns 9 percent to 13 percent more than the average for students who these data are derived from the annual october supplement to the current population survey. they are summarized in the u. s. department of education ’ s condition of education 2007 available at http : / / nces. ed. gov / programs / coe / 2007 / section3 / indicator 25. asp # info. socioeconomic status was measured by a composite score on parental education and occupations and family income. the study also found that the proportion of low - scoring math students from high socioeconomic families who completed at least a bachelor ’ s degree was 30 percent versus only 3 percent for those from lower socioeconomic families. for those in the middle quintiles of both scores and family characteristics, the proportion was 21 percent. ended their education with high school. those who completed a two - year associate degree earn an even larger premium, 15 percent to 27 percent ( kane and rouse, 1999 ). and the earnings of graduates who started at two - year schools and transferred to four - year programs ultimately match those who begin their post - high - school education at four - year institutions ( gill and leigh, 2003 ). community colleges play a constructive role not only for 18 - to - 22year - olds but also for older adults, providing flexible programs for obtaining new skills, specialized training contracted for by individual businesses, remedial education, and adult enrichment. adult education today we are increasingly recognizing that education need not, indeed should not, stop at the age of 22. economists have long argued that on - the - job training and learning - by - doing are significant components of the acquisition of human capital. research shows that the knowledge and experience gained over time through informal and formal learning on the job appear to pay off for workers and accrues particularly rapidly early in their careers ( altonji and williams, 2005 ; topel, 1991 ). an extensive survey of firm - sponsored training a number of years ago found that 84 percent of employees received some kind of formal training while working for their current employer, and 96 percent received some type of informal

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