In Part 1, we established that floating exchange rates don't insulate economies from the Global Financial Cycle (GFC). But what drives this cycle? The data points to one prime suspect: The VIX Index.
Not Just a US Index
The VIX measures expected volatility in the S&P 500. Technically, it's just about US stocks. But empirically, it acts as a thermometer for the entire global financial system.
When the VIX is low, it signals 'risk-on'. When it spikes, it signals 'risk-off'. And because the US Dollar is the global funding currency, US risk appetite determines global liquidity.
The Transmission Mechanism
The mechanism works through the balance sheets of global banks. As shown by Bruno & Shin (2015), global banks act like disciplined risk-takers regarding their leverage.
- Low VIX: Perceived risk falls. Banks borrow more (leverage up) to lend globally.
- High VIX: Perceived risk spikes. Banks contract their balance sheets (deleverage) to protect equity.
This creates a synchronized expansion and contraction of credit. When Wall Street sneezes, credit lines in Emerging Markets freeze globally.
The Data Reality
My analysis of 20 years of data (2001-2023) confirms this strong negative correlation. A shock to the VIX leads to an immediate and significant drop in cross-border capital flows.
Interestingly, this relationship has weakened slightly post-COVID, likely due to stricter banking regulations (Basel III) that prevent banks from leveraging up too aggressively during calm periods.
But the core truth remains: The VIX is arguably the most important number in the global economy.
In Part 3, we bring it home: What does this mean for a small open economy like Denmark?
Footnotes
- Bruno, V., & Shin, H. S. (2015). Cross-Border Banking and Global Liquidity. Review of Economic Studies. ↩