(CBS) Reflecting its eroding economic fortunes, the American middle-class is often described as having been "hollowed out." New employment data suggest that isn't just a figure of speech.

Although 60 percent of the jobs lost following the 2008 financial crisis were in mid-wage occupations such as construction, manufacturing and office management, relatively few of those positions have come back, according to the National Employment Law Project. Instead, most of the jobs created during the U.S. economy's fitful recovery -- 58 percent -- have been in low-wage professions including retail sales, food preparation, home health and customer service, the New York-based advocacy group said Friday in a report.

Read more: CBS News