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Unprecedented Divergence in Three Decades: US Stock Index Volatility Hits Historic Low Since 1960s, While Single-Stock Swings Surge to Seven Times the Benchmark
The VIX Index is a calculation designed to produce a measure of constant, 30-day expected volatility of the U.S. stock market, derived from real-time, mid-quote prices of S&P 500 Index options.
Assuming the VIX is 15, it means that the expected annual volatility of the S&P 500 in the next 30 days is 15%.