In a depressing new report, two Rutgers professors predict that it will take more than seven years to restore the health of the nation’s labor market to prerecession levels.

The report, released on Wednesday, says that even if the nation adds more than two million jobs annually over the next seven years, that will barely offset what the authors see as a giant employment deficit.

The large employment deficit, the report says, was created by the loss of 7.1 million private-sector jobs since the recession began in December 2007 and by the economy’s failure to keep up with labor-force growth — that is, the increasing number of people who want jobs — during the recession.

“America faces a troubling arithmetic of employment recovery because of the extreme depth of the employment deficit it now faces,” the report says. “It may take the nation until the second half of the next decade to return to the prerecession labor market conditions of 2007. Such a long road back is likely to be necessary if the nation is able to achieve above-average annual employment growth for a sustained period of time.”

The report, “America’s New Post-Recession Employment Arithmetic,” was written by James W. Hughes, dean of the Edward J. Bloustein School of Planning and Public Policy, and by Joseph J. Seneca, university professor and an economist at the Bloustein School.

The report gives a failing grade to job growth over the last decade, calling it “The Lost Employment Decade.” Noting that there are 1.256 million fewer private-sector jobs than in December 1999, it said the nation was “destined to exit the decade with fewer jobs than when it began.”

Dean Hughes and Professor Seneca contrasted this decade with the 1990s, when the number of private-sector jobs climbed by 19.2 million, and with the 1980s, when the nation added 16.2 million private-sector jobs.

To return to the labor market conditions of 2007, the report said the nation would not only need to offset the 1.3 million annual increase in the labor force, but would also need to compensate for the job losses suffered during the recession. Given conservative estimates of further declines in employment, the Rutgers professors see an overall employment deficit of 9.4 million private-sector jobs by December 2009.

“Erasing this deficit will require substantial and sustained employment growth,” the report said. Even with an optimistic picture for job growth, the report said, it will take years before the nation returns to prerecession labor market conditions.

The report notes that the economic expansion from November 2001 to December 2007 added 6.2 million private-sector jobs, or 1.0 million a year. It compared that with the creation of 21.5 million private-sector jobs during the expansion from March 1991 to March 2001, coming to 2.15 million a year, and the addition of 18.4 million private-sector jobs during the economic expansion from November 1982 to July 1990, amounting to 2.4 million jobs per year.

“Even if the nation could add 2.15 million private-sector jobs per year starting in January 2010,” the report said, “it would need to maintain this pace for more than 7 straight years (7.63 years), or until August 2017, to eliminate the jobs deficit!”

This, the authors noted, might be optimistic. Those hoped-for 7.63 years of consecutive job growth would be about 50 percent longer than the average length — 58 months — of every economic expansion since World War II.