Health care and social assistance jobs will be the fastest-growing sectors, accounting for one quarter of the 20.2 million new jobs the economy is expected to generate by 2020.

Retiring baby boomers will help open up an additional 33.8 million positions for total vacancies of 54 million, the Labor Department said on Wednesday in its biannual Employment Outlook report for job growth between 2010 and 2020.

During the recent recession, employment declined by 7.8 million jobs to a total of 129.8 million in 2010. The report does not estimate by what year those jobs will be replaced.

In addition, the workforce is getting older. Despite the retirement surge, a slowdown in population growth means that the post-World War II baby boomers will make up a quarter of all U.S. workers by 2020, up from 19.5 percent today.

Hispanics, meanwhile, are joining the workforce at a fast pace. They will represent 18.6 percent of overall employment by decade's end, up from 14.8 percent today. In contrast, Asians and African-Americans will see their share in the labor force rise by 1 percentage point or less to 5.7 percent and 12 percent, respectively.

"The labor force is projected to get older, become racially and ethnically more diverse and show a small increase in women as a share of the total," the department said.

Professional and business services will be the second-fastest growing industry, adding 3.8 million positions.

It will be followed by construction, although the 1.8 million new construction jobs will not bring employment in the industry back to levels seen during the housing boom.

SKILLS DIVIDE

The report also spelled out the skills workers of the future will need.

Two thirds of the total job openings will require only a high-school education or less, it said. For example, there will be roughly 70 percent growth in personal care aides and health-care support employment, the fastest-growing occupations. No high school diploma would be required, and workers would get short, on-the-job training.

At the same time, demand for people with master's degrees will increase by 21.7 percent, the Labor Department said.

The manufacturing sector and the federal government will both lose jobs over the next decade.

(Reporting by Stella Dawson; Editing by Andrea Evans)

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