The Social Security Administration projects that its trust funds will be depleted by 2033—not an optimistic forecast. But it may be even bleaker than that.

New studies from Harvard and Dartmouth researchers find that the SSA's actuarial forecasts have been consistently overstating the financial health of the program's trust funds since 2000.

"These biases are getting bigger and they are substantial," said Gary King, co-author of the studies and director of Harvard's Institute for Quantitative Social Science. "[Social Security] is going to be insolvent before everyone thinks."

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The Social Security and Medicare Trustees' 2014 report to Congress last year found trust fund reserves for both its combined retirement and disability programs will grow until 2019. Program costs are projected to exceed income in 2020 and the trust funds will be depleted by 2033 if Congress doesn't act. Once the trust funds are drained, annual revenues from payroll tax would be projected to cover only three-quarters of scheduled Social Security benefits through 2088.



Researchers examined forecasts published in the annual trustees' reports from 1978, when the reports began to consistently disclose projected financial indicators, until 2013. Then, they compared the forecasts the agency made on such variables as mortality and labor force participation rates to the actual observed data. Forecasts from trustees reports from 1978 to 2000 were roughly unbiased, researchers found. In that time, the administration made overestimates and underestimates, but the forecast errors appeared to be random in their direction.

"After 2000, forecast errors became increasingly biased, and in the same direction. Trustees Reports after 2000 all overestimated the assets in the program and overestimated solvency of the Trust Funds," wrote the researchers, who include Dartmouth professor Samir Soneji and Harvard doctoral candidate Konstantin Kashin.

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The administration's Office of the Chief Actuary produces the forecasts. Stephen Goss, the chief actuary since 2001, was unavailable to comment and has not seen all of the new research, an administration spokesman said.

However, Goss published a 2013 note that outlined the SSA's projection methodologies. The note was written in response to 2012 research by King and Soneji that found the Social Security Administration underestimated how long Americans will live and projected that the trust funds would be depleted by 2031, two years earlier than the government has estimated.

"The projections developed by the Office of the Chief Actuary for the Trustees Reports are intended to reflect all aspects of future possible trends in demographic, economic, and programmatic factors, given current Social Security law," Goss and other SSA officials wrote. King and Soneji's projections "were within the range of reasonable uncertainty as specified in the Trustees Report, and therefore should cause no alarm."