The provision that gives the name of America’s most popular retirement savings plan, section 401(k), will turn 40 this Tuesday. And in its first four decades, the 401(k) has lived an unexpectedly glamorous life. At the time of its enactment, lawmakers anticipated that it would exist in obscurity, affecting only a small number of corporate executives. Forty years later, 401(k) has become possibly the most famous section of the Internal Revenue Code, with well over 90 million Americans personally participating in 401(k)s or similar defined contribution plans.

Section 401(k)’s rise from obscurity to ubiquity might suggest that its 40th birthday should be an occasion for celebration. But this is no time for popping corks. The provision has proven to be enormously expensive while also ineffective at helping most American workers save for retirement. In short, section 401(k) is facing something of a mid-life crisis.

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