Another source of alarmism is the Census Bureau's Current Population Survey, which suggests that Americans receive little income from individual retirement accounts and 401(k) plans and are increasingly dependent on Social Security. But the survey's measure of retirement income excludes the unscheduled, as-needed withdrawals from IRAs and 401(k)s that are the primary way Americans draw down their accounts. Thus the census figures omit most of the income from such saving methods, an error that becomes ever more important as an ever-larger percentage of Americans uses them. So while the survey seems to show a growing problem, all it really shows is an increasingly large methodological flaw. Already it isn't counting 60 percent of income from retirement plans.

That doesn't mean that there's nothing at all to worry about. Social Security fails to keep all the elderly out of poverty, which is rather amazing considering how much it spends. Certain groups, such as single women with no education past high school, have a high risk of ending up poor in old age. Biggs favors a reform of the system that creates a flat, universal benefit. It would be set high enough to keep all senior citizens out of poverty, but low enough to make the system solvent and to create a stronger incentive for middle-income and high earners to save more for their retirement. Data from the Organization for Economic Cooperation and Development shows that the more generous government benefits are for the elderly, the less people generate their own retirement income through work and saving.

And then there's the fact that Social Security itself faces a financing shortfall with a net present value exceeding $10 trillion. That is a genuine problem — but not one, of course, that can be solved by expanding the program's benefits.