CBOE Volatility Index

The VIX is called the 'fear gauge' of Wall Street. It measures how nervous investors are about the stock market over the next 30 days. A low VIX (below 15) means calm markets. A high VIX (above 25) means investors are scared.

When the VIX rises, investors are scared. Scared investors sell stocks and buy safe things — and gold is one of the safest things they can buy. When the VIX falls, investors feel confident. They move money back to stocks and sell gold. Think of gold as the 'panic room' of investing. The VIX tells you how many people are heading for it.