But depending on how underemployment is defined, that number could change to one out of every three workers, says the study titled "I have a Job, But ..." published in the Journal of Management.
Co-author Frances McKee-Ryan, an assistant professor at the University of Nevada, said no matter what definition is used, "All reflect a job that is substandard in some way, and all have potentially detrimental effects on individuals and our society."
A number of different work conditions can define underemployment, from holding a job below a worker's skill level to working fewer hours than might be desired.
The unemployment rate has been falling in recent months, but the study says the number of underemployed persons is rising.
"Underemployment is quite prevalent across the board in our current economic conditions and is linked to a broad range of negative outcomes for employees. … As a society, we need to be concerned with creating high-quality jobs for our increasingly educated population as the economy improves following this recession," McKee-Ryan said in a statement.