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Panic of 1907

Bank Runs, Confidence, and Solvency in 1907

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What Do Bank Runs in 1907 Reveal About Confidence and Solvency?

The bank runs of 1907 are not merely historical curiosities—they are case studies in one of the most fundamental problems in financial economics: the self-fulfilling nature of banking panics. A bank that is fundamentally solvent can be destroyed by a bank run if the run is large enough, because the forced liquidation of assets at distressed prices can convert temporary illiquidity into actual insolvency. This possibility—that a panic can create the catastrophe it predicts—is the central puzzle of bank run dynamics, and the 1907 crisis illustrates it with unusual clarity. Understanding the economics of 1907's bank runs illuminates both the specific events and the more general problem of financial system stability.

Quick definition: Bank run economics in 1907 refers to the self-reinforcing dynamics by which depositor withdrawal decisions created the conditions that validated those decisions—with the distinction between illiquid-but-solvent institutions (worth rescuing) and genuinely insolvent ones (not worth rescuing) being the critical assessment that Morgan had to make under extreme pressure and with limited information.

Key takeaways​

  • A bank run is a coordination failure: if all depositors try to withdraw simultaneously, a solvent bank can be forced into suspension; if none try, the bank is fine.
  • The first-mover advantage in a bank run creates incentives to run even if you believe the bank is fundamentally sound, because you don't want to be the last depositor behind others who ran first.
  • The illiquid-but-solvent versus genuinely-insolvent distinction is critical for crisis management: rescuing an illiquid solvent bank with liquidity stops the cascade; rescuing an insolvent bank wastes resources.
  • The same information that triggers a run (news of one institution's difficulties) is not sufficient to determine whether that institution is solvent—the assessment requires examining assets and liabilities under time pressure.
  • Deposit insurance breaks the run dynamic by eliminating the first-mover advantage: if your deposits are guaranteed regardless, there is no reason to run.
  • The 1933 introduction of FDIC deposit insurance was the most effective single reform for preventing bank runs, directly addressing the mechanism the 1907 panic illustrated.

The self-fulfilling nature of bank runs​

A bank is inherently illiquid: it borrows short (deposits can be withdrawn at any time) and lends long (mortgages and business loans mature over years). In normal conditions, this maturity mismatch is sustainable because depositors as a group do not demand simultaneous withdrawal—they continuously roll over their deposits and the bank continuously rolls over its loan book.

A bank run occurs when a sufficient number of depositors simultaneously attempt to withdraw, overwhelming the bank's available cash. The question of whether a bank "survives" a run is partly about its solvency (whether its assets exceed its liabilities) and partly about the speed at which it can liquidate assets to meet withdrawal demands.

The self-fulfilling dynamic arises because a bank that is fundamentally solvent can be made insolvent by a run. If forced liquidation of loans and securities generates cash at prices significantly below their full value (because distressed selling drives prices down), the bank may exhaust its assets before satisfying all depositors. The run that was triggered by fear of insolvency causes the insolvency it feared.

The first-mover advantage​

Individual depositors facing uncertainty about their bank's soundness face a specific strategic situation: if the bank is sound, withdrawing wastes effort but doesn't matter; if the bank might fail, withdrawing first ensures full recovery while others might get nothing. This asymmetry creates a dominant strategy—withdraw when uncertain—that produces runs even when most depositors believe the bank is probably sound.

The first-mover advantage is what makes bank runs self-reinforcing: each person who runs reduces the probability that late-coming depositors can be paid in full, increasing the incentive for others to run before them. A run can accelerate from nothing to complete collapse in hours once the self-reinforcing dynamic is triggered.

In 1907, the Knickerbocker's run exemplified this dynamic: once the National Bank of Commerce refused to clear Knickerbocker checks (signaling concern about the institution's soundness), each depositor who delayed withdrawal was taking a risk that depositors who ran first would not be taking. The rational individual response—withdraw immediately—was collectively destructive.

Morgan's solvency assessment​

Morgan's crisis management required making the illiquid-versus-insolvent assessment quickly and under extreme pressure. His decision not to rescue the Knickerbocker (implicitly judging it insolvent or irremediably compromised) and to rescue the Trust Company of America (judging it solvent-but-illiquid) was the central strategic decision of the entire crisis.

Getting this distinction wrong in either direction has costs. Rescuing a genuinely insolvent institution wastes limited resources and merely delays failure while consuming funds needed elsewhere. Failing to rescue a solvent-but-illiquid institution allows the self-fulfilling mechanism to convert illiquidity into insolvency, destroying real value unnecessarily.

Morgan's assessment was necessarily rough—a full examination of a trust company's books, even by a team of skilled accountants, would take weeks; Morgan had hours. His judgment drew on knowledge of the specific institutions' management, loan portfolios, and connections to the speculative interests that had triggered the crisis.

Deposit insurance as a solution​

The Federal Reserve's lender-of-last-resort function addressed the bank run problem by providing emergency liquidity to illiquid-but-solvent banks, preventing forced liquidation from converting illiquidity into insolvency. But the Fed's function requires the illiquid-versus-insolvent distinction to be made correctly—and that distinction is difficult under pressure.

Deposit insurance, introduced through the FDIC in 1933, addressed the bank run problem more directly by eliminating the first-mover advantage that drives runs. If deposits are guaranteed regardless of whether the bank fails, there is no incentive to be first in line—waiting is as safe as running. FDIC insurance has dramatically reduced the frequency of retail bank runs in the United States since its introduction.

The 2008 crisis demonstrated that deposit insurance, while effective for retail banks, does not prevent runs on wholesale funding markets (money market funds, repo markets) that serve similar economic functions but are not covered by deposit insurance. The money market fund runs of 2008—triggered by the Reserve Primary Fund breaking the buck—were precisely the type of self-fulfilling run that the FDIC prevents in retail banking.

Real-world examples​

The bank run dynamics of 1907 appear in structurally identical form in multiple modern episodes. The Northern Rock bank run of 2007 was triggered by the news that Northern Rock had borrowed from the Bank of England's emergency facility—news that signaled weakness, triggering the first-mover dynamic, despite Northern Rock being fundamentally solvent at the time. The FDIC-equivalent guarantee of British deposits was not sufficiently well-publicized to break the first-mover dynamic.

The 2023 Silicon Valley Bank run was similarly driven by social media amplification of concern about SVB's bond portfolio losses, producing a modern bank run that unfolded faster than 1907 runs because digital communication and digital transactions removed the physical queuing constraint that had previously limited run speed.

Common mistakes​

Treating bank runs as irrational. Individual depositors making rational self-interested decisions cause collectively irrational outcomes. The run is individually rational (withdraw before others) even though collectively destructive. This distinction matters for policy design: attacking the irrationality narrative misses the coordination problem that is the real issue.

Assuming deposit insurance fully solves the problem. FDIC insurance addresses retail bank runs effectively but does not cover wholesale funding markets, money market funds, or shadow banking entities. The 2008 crisis demonstrated that run dynamics persist in the uninsured sectors.

Treating Morgan's solvency assessments as definitively correct. Morgan made the best assessments possible under extreme time constraints with limited information. Whether the Knickerbocker was truly insolvent or whether a rescue could have succeeded is genuinely uncertain.

FAQ​

Is deposit insurance available internationally?​

Most developed countries have some form of deposit insurance. The coverage limits and institutional arrangements vary. The FDIC in the United States currently covers deposits up to $250,000 per depositor per institution. Information about specific coverage arrangements is available from the FDIC at fdic.gov.

What prevents bank runs on money market funds today?​

The SEC implemented rules after the 2008 money market fund crisis that allow money market funds serving institutional investors to float their net asset values rather than maintaining a constant $1 price, reducing the first-mover advantage. Additional liquidity requirements and redemption gate provisions provide further protections. The rules have been updated subsequently.

Can social media accelerate bank runs to dangerous speeds?​

The 2023 SVB run demonstrated that social media can significantly accelerate bank run dynamics—the run occurred within 24 hours rather than over days or weeks as in 1907. This speed creates new challenges for crisis management that rely on assessing institutions' solvency before the run exhausts their liquidity.

Summary​

The bank runs of 1907 illustrate the fundamental economics of banking panics: a coordination failure in which rational individual decisions to withdraw produce collectively irrational outcomes, and the self-fulfilling possibility that a run can convert illiquidity into insolvency by forcing distressed asset liquidation. Morgan's crisis management required the crucial distinction between illiquid-but-solvent institutions (worth rescuing with emergency liquidity) and genuinely insolvent ones (not worth rescuing). The lender-of-last-resort function the Fed provides addresses the illiquidity mechanism; deposit insurance addresses the first-mover advantage that triggers runs. Both solutions were designed in direct response to the dynamics the 1907 panic demonstrated, and both remain essential elements of modern financial stability architecture.

Next​

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