U.N. data shows that U.M. labor force participation was lower than expected in May.
The unemployment rate was 9.9 percent.
The Bureau of Labor Statistics report was released Wednesday, and showed that the number of people who said they had been unemployed for six months or more rose to 8.8 million.
That was more than 1 million people below the 8.6 million who were jobless for that time.
The unemployment rate rose to 9.7 percent in May from 8.5 percent in April, the BLS said.
The increase in the labor force also was much lower than the overall increase in job openings.
The Labor Department said the labor market added 9,000 jobs last month.
The report said the average weekly earnings of Americans working full-time fell 2 cents to $18,400 in May, a drop of 2.3 percent from the previous month.
That was a drop from the 5.7-cent decline the previous week.