Leverage Cascade

A leverage cascade is the self-amplifying feedback loop in which asset price declines force leveraged institutions to sell assets, which further depresses prices, which forces further selling — a positive feedback mechanism that converts small initial shocks into large systemic collapses. It is the dominant propagation channel in financial contagion: without leverage, an asset price decline produces a proportional loss; with leverage, the same decline produces a loss multiplied by the leverage ratio, potentially triggering margin calls that force fire-sale liquidations.

The mathematics is simple but unforgiving. An institution with 10:1 leverage holds $10 of assets for every $1 of equity. A 10% decline in asset values wipes out the equity entirely. To prevent this, the institution must sell assets as prices fall — but if many institutions share the same leverage and the same assets, the coordinated selling depresses prices faster than any individual institution can escape. The result is a deleveraging spiral in which rational self-preservation at the individual level produces collective self-destruction at the system level. Leverage cascades are not caused by panic or irrationality; they are caused by the arithmetic of coupled balance sheets operating under joint constraints.