The number of Americans who have been investigated and deemed eligible for access to classified information rose last year to a total of 5,150,379 as of October 2013. It was the fourth consecutive year of growth in the security-cleared population.

The new total includes civilian and military government employees (3.7 million) and contractor personnel (1 million), as well as indeterminate others (0.4 million). It represents an increase of 4.7% from the previous year’s total of 4.9 million. Of the 5.1 million persons who were found eligible for access to classified information, 60% had access in fact.

An Office of Management and Budget review said that the continuing growth of the security clearance system is problematic both for financial and security reasons.

“[The] growth in the number of clearance-holders increases costs and exposes classified national security information, often at very sensitive levels, to an increasingly large population,” said the OMB review, which was released last week.

Accordingly, the OMB review recommended that the government “reduce [the] total population of 5.1M Secret and TS/SCI clearance holders to minimize risk of access to sensitive information and reduce cost.”

The number of security clearances is supposed to be reported to Congress each year by the Office of the Director of National Intelligence. But ODNI said it has not yet filed its 2013 report. [Update: The report is available here.] However, the data were provided in the OMB review.

“Since 9/11, the number of clearances annual approved by DoD [the Department of Defense] has tripled, and continues to grow,” according to an independent review of the Washington Navy Yard Shooting in September 2013 that was also released last week.

“This growth magnifies the challenge of investigating clearance seekers, judging their applications, and periodically reviewing them after they are approved.”

“The continuing expansion of the cleared population has created a culture in which once-rare security clearances are now too often granted by default.” (Actually, security clearances have not been “rare” for quite a few decades.)

The independent review proposed that “DoD should seek to make a 10 percent cut in the number of positions that require access to material classified as Secret.”

“As soon as this reduction is attained, a follow-on review should determine whether further reductions can be realized.”

The independent review also identified “a growing culture of over-classification” as a related issue that “merit[s] additional focused study.” See Security From Within: Independent Review of the Washington Navy Yard Shooting, Department of Defense, November 2013 (released March 18, 2014).

Another review conducted by the Under Secretary of Defense for Intelligence concurred that there are too many people with security clearances. But it said that reducing the cleared population will not necessarily improve quality control or significantly reduce the burden on background investigators and adjudicators, because they are also responsible for a large number of “suitability” investigations in addition to security clearance investigations.

“The workload challenge will not be eliminated by reducing the number of security clearances because of the pending impacts of the alignment of suitability and security investigations and reinvestigations required by Executive Order 13467 and the 2012 Revised Federal Investigative Standards.”

“The net effect of the new standards will be to increase the Department’s investigative and adjudicative workload, regardless of the number of security clearances.” See Internal Review of the Washington Navy Yard Shooting, Report to the Secrecy of Defense, November 20, 2013.

Last week, the Department of Defense issued updated policy on the DoD Personnel Security Program (PSP), DoD Instruction 5200.02, March 21, 2014.

Among other things, the updated policy dictates that “All personnel in national security positions shall be subject to continuous evaluation,” referring to a process of collecting, reporting and evaluating security-relevant information about cleared individuals on an ongoing basis.

But this policy is aspirational rather than descriptive of current practice, which is limited to small-scale pilot projects to develop such a capacity. Full implementation of the “continuous evaluation” process is at least several years away, according to last week’s OMB report.

Secretary of Defense Chuck Hagel said last week that “We will consider reducing the number of personnel holding Secret security clearances by at least 10 percent, a recommendation in line with the October 2013 guidance from the Director of National Intelligence.”

Reducing the number of “personnel” that hold security clearances is a slightly different objective than reducing the number of “positions” that require access to classified information, as recommended by the Independent Review. It is not clear if the Secretary intended to make such a distinction.

In response to a request from Secrecy News, ODNI public affairs refused to provide a copy of the October 2013 DNI guidance. (Update: The DNI guidance was described further in this article from Politico.)