Last week the federal government ended the fiscal year with a reported deficit of approximately $400 billion, pushing the federal debt held by the public to nearly $4 trillion. Sobering though these numbers are, they actually understate the problem. Through an accounting sleight of hand with far greater consequences than the corporate scandals of recent years, the federal government distorts public debate, threatens social programs and impoverishes future generations.
What's missing from the $400 billion figure is an accurate recognition of the mounting obligations of the Social Security system. Under current practices, Social Security reports its financial performance on a cash-flow basis: it compares annual revenues to annual costs and reports a surplus or a deficit. Last year, Social Security enjoyed a surplus of roughly $160 billion. The government used this money to mask what would otherwise have been a $560 billion federal deficit.
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Were the federal government to account for its Social Security obligations under the rules of accrual accounting, which govern public companies, its financial outlook would be far worse. By the end of last year, the Social Security system owed retirees and current workers benefits valued at $14 trillion. The system's assets, in contrast, were only $3.5 trillion. These assets include not only the trust funds' current reserves ($1.4 trillion), but also the present value of the taxes that current workers will pay over the remainder of their working lives ($2.1 trillion).
In other words, the system's current shortfall — its assets minus its liabilities — is $10.5 trillion. Unless Congress chooses to rescind Social Security benefits that have already been earned, this shortfall must be shouldered by future generations. This implicit debt of the Social Security system is more than two and a half times larger than the government's public debt.
http://www.nytimes.com/2003/10/09/opinion/09JACK.html