Understanding the Social Security Trust Funds
October 5, 2010
Few budgetary concepts generate as much unintended confusion and deliberate misinformation as the Social Security trust funds. Political candidates of both parties have accused their opponents of “raiding” the trust funds. Some writers disparage the trust funds as “funny money” or “IOUs.” All these claims are nonsense. In fact, the Social Security trust funds are invested in Treasury securities that are every bit as sound as the U.S. government securities held by investors around the globe; investors regard those securities as being among the world’s very safest investments. This brief paper provides some basic information about the Social Security trust funds.
How Do the Trust Funds Work?
Social Security’s financial operations are handled through two federal trust funds — the old-age and survivors insurance (OASI) trust fund and the disability insurance (DI) trust fund. Although legally distinct, they are often referred to collectively as “the Social Security trust fund.” All of Social Security’s payroll taxes and other earmarked income are deposited in the trust funds, and all of Social Security’s benefits and administrative expenses are paid from the trust funds.
In years when Social Security collects more in payroll taxes and other income than it pays in benefits and other expenses — as it has each year since 1984 — the Treasury invests the surplus in interest-bearing Treasury bonds and other Treasury securities. Social Security can redeem these bonds whenever needed to pay benefits. The balances in the trust funds thus provide legal authority to pay Social Security benefits when the Social Security program’s current income is insufficient by itself.
What Is the Trust Funds’ Financial Status?
Social Security is adequately financed in the short term but faces a modest long-term financial shortfall amounting to 0.7 percent of gross domestic product (GDP) over the next 75 years, the period that the program’s actuaries use in evaluating the program’s long-term finances.  Social Security has run a surplus in every year since 1984, as was anticipated when Congress enacted and President Reagan signed the legislation based on the recommendations of the Greenspan Commission in 1983. The authors of the 1983 legislation purposely designed program financing in this manner to help pre-fund some of the costs of the baby boomers’ retirement.
Under current projections, the combined Social Security trust funds will continue to run annual surpluses until 2025. The interest income that the trust funds earn on their bonds, as well as the proceeds the trust funds will receive when their bonds are redeemed, will enable Social Security to keep paying full benefits until 2037.
In 2037, the trust funds are projected to run out of Treasury bonds to cash in. At that point, if nothing else is done, Social Security could still pay more than three-quarters of its scheduled benefits using its annual tax income. Contrary to a common misunderstanding, benefits would not stop. Of course, paying three quarters of promised benefits is not an acceptable way to run the program, and Congress should take action well before 2037 (with sooner being better than later) to restore long-term solvency to this vital program.
How Are the Trust Funds Invested?
The Social Security trust funds are invested entirely in U.S. Treasury securities. Like the Treasury bills, notes, and bonds purchased by private investors around the world, the Treasury securities that the trust funds hold are backed by the full faith and credit of the U.S. government. The U.S. government has never defaulted on its obligations, and investors consider U.S. government securities to be one of the world’s safest investments.
The Treasury securities held by the trust funds have some special features that make them even more attractive investments than other Treasury securities. First, the trust funds’ investments do not fluctuate in value and can always be redeemed at par. Even if the securities must be redeemed early, Social Security is guaranteed not to lose money on its investment. Second, all of the securities purchased by the trust funds — even short-term securities that will mature in one or two years — earn interest at the same rate as medium- and long-term Treasury securities (those not due or callable for at least four years).
By the end of 2009, the trust funds had accumulated over $2.5 trillion worth of Treasury securities, earning an average interest rate of 4.9 percent during that year. The annual report of Social Security’s board of trustees lists the specific securities owned by the trust funds, their maturities, and interest rates. The trustees project that the trust funds will earn $118 billion in interest income in 2010. 
Is the Federal Government “Raiding” the Trust Funds?
No. Some critics have suggested that the lending of Social Security trust fund reserves to the Treasury represents a misuse of those funds. This view reflects a misunderstanding of how the Treasury manages the federal government’s finances.
When the rest of the budget is in deficit, a Social Security cash surplus allows the government to borrow less from the public to finance the deficit. (The “public” encompasses all lenders other than federal trust funds, including U.S. individuals and institutions, the Federal Reserve System, and foreign investors.) The Treasury always uses whatever cash is on hand — whether from Social Security contributions or other earmarked or non-earmarked sources — to meet its current obligations before engaging in additional borrowing from the public. There is no sensible alternative to this practice. After all, why should the Treasury borrow funds when it has cash in the till?
Back in 1938, the first Advisory Council on Social Security — a group of independent experts appointed to review the program’s long-term finances — firmly endorsed the investment of Social Security surpluses in Treasury securities:
The United States Treasury uses the moneys realized from the issuance of these special securities by the old-age reserve account in the same manner as it does moneys realized from the sale of other Government securities. As long as the budget is not balanced, the net result is to reduce the amounts which the Government has to borrow from banks, insurance companies and other private parties. When the budget is balanced, these moneys will be available for the reduction of the national debt held by the public. The members of the Advisory Council are in agreement that the fulfillment of the promises made to the wage earners included in the old age insurance system depends upon, more than anything else, the financial integrity of the Government. The members of the Council, regardless of differing views on other aspects of the financing of old-age insurance, are of the opinion that the present provisions regarding the investment of the moneys in the old-age reserve account do not involve any misuse of these moneys or endanger the safety of these funds.
Other Advisory Councils have reached the same conclusion.
Money that the federal government borrows from the public or from Social Security is used to finance the ongoing operations of the government in the same way that money deposited in a bank is used to finance spending by consumers and businesses. In neither case does this represent a “raid” or misuse of the funds. The bank depositor will get his or her money back when needed, and so will the Social Security trust funds.
When Social Security needs to start cashing in its holdings of Treasury securities to meet its benefit obligations, the federal government will have to increase its borrowing from the public, or raise taxes or spend less. That will be a concern for the Treasury — but not for Social Security, as long as the solvency of the federal government itself is not called into question. Social Security will be able to sell its bonds just as any private investor might do.
Would Investing the Trust Funds in Other Financial Assets Change the Situation?
No. Although some people have argued that the Social Security trust funds would be more “real” if they were invested in private stocks or bonds, there is nothing to this contention. If there were no change in the total federal budget deficit, such a policy would merely rearrange the holding of assets in the economy and would not change the net financial situation of Social Security, the federal government as a whole, or the private sector. As the Congressional Budget Office has explained:
Clearly, investing trust funds in private investments could have no significant impact on the government’s overall balance sheet. If the Treasury were cut off from access to trust fund moneys, it would have to sell more securities (bills, notes, and bonds) in the credit markets. At the same time, federal trust funds would accumulate more financial assets. Net federal indebtedness — liabilities minus assets — would be little different than under the current arrangement. Conversely, private investors would have to buy more Treasury debt than under current arrangements but would face a shrunken supply of the assets purchased by the trust funds. The upshot would be a rearrangement of public and private portfolios, perhaps accompanied by a small change in the relative returns on various financial instruments.
For example, if the Social Security trust funds were to invest $100 billion in corporate stock, the Treasury would need to finance the non-Social Security deficit by borrowing $100 billion more in private credit markets. As a result, the private sector would hold $100 billion less in equities and $100 billion more in government debt. Neither the government nor the private sector would be better or worse off.
Last but not least, investing the trust funds in private stocks and bonds would subject the trust funds to a much greater degree of risk. Holding corporate equities seemed appealing several years ago, when the stock market was hitting new highs, but the more recent turmoil in financial markets has made it much less attractive today.
Is Trust Fund Debt Real if It’s Not Part of Debt Held by the Public?
CBPP and other budget experts generally focus on debt held by the public — which reflects what the government must borrow in private credit markets and which excludes trust fund holdings — as the most useful measure of federal debt for economic analysis.  Some have argued that it is inconsistent to adopt that focus while simultaneously viewing the debt held by Social Security as real.
This argument is incorrect: both measures of debt are important, but they measure different things.
Debt held by the public is a measure of the federal government’s overall fiscal health. It represents money that must be borrowed and periodically refinanced in private credit markets; interest payments on that debt represent a current drain on government resources. If the specter of excessive debt led investors to lose confidence in U.S. government securities, federal interest costs could increase substantially, with potentially troubling implications for U.S. and world economies.
Debt held by Social Security, by contrast, provides information about the adequacy of the program’s dedicated financing. Debt held by trust funds does not have the same broader economic significance as debt held by the public. Since it does not need to be financed in private credit markets, it cannot lead to a refinancing crisis. As legal authority to spend money in the future, it is essentially similar to legal authority to meet spending commitments for other entitlement programs that are not financed through trust funds and are not included in measures of federal debt. In addition, an increase in trust fund balances that provides authority for higher Social Security expenditures in some distant year is not equivalent to issuing more publicly held debt to finance additional spending today. If additional spending authority leads to more federal borrowing at some time in the future, that borrowing will add to debt held by the public when that spending occurs.
As the 1938 Advisory Council on Social Security wrote in the passage quoted above, “The fulfillment of the promises made to the wage earners included in the old age insurance system depends upon, more than anything else, the financial integrity of the Government.” Protecting Social Security therefore requires not only assuring that the program itself is adequately financed but also putting the overall federal budget on a sustainable long-term course.
 “Tired Old Trust Fund Bunk,” FactCheck.org, October 25, 2006,http://www.factcheck.org/article459.html; Denison Smith and Peter Ferrara, Stop the Raid, Social Security Foundation, 2008; Jon Ralston, “It’s hard to dodge the candidates’ verbal gaffes,” Las Vegas Sun, August 13, 2010, http://www.lasvegassun.com/news/2010/aug/13/its-hard-dodge-candidates-verbal-gaffes/ .
 Allan Sloan, “Social Security, the trust fund and funny money,” Washington Post, August 10, 2010.
 Kathy A. Ruffing and Paul N. Van de Water, What the 2010 Trustees’ Report Shows about Social Security, Center on Budget and Policy Priorities, August 13, 2010.
 2010 Annual Report of the Board of Trustees of the Federal Old-Age and Survivors Insurance and Disability Insurance Trust Funds , pages 5, 43, and 149-150, http://www.ssa.gov/OACT/TR/2010/tr2010.pdf.
 Dean Baker, “Social Security Trust Fund: It’s Real,” Beat the Press, August 12, 2010, http://www.cepr.net/index.php/blogs/beat-the-press/social-security-trust-fund-its-real .
 Congressional Budget Office, Federal Debt and Interest Costs, May 1993, pp. 33-4.