Volatility
The magnitude and speed of price fluctuations in a stock or market index. Higher volatility means larger price swings; lower volatility means more stable prices.
Volatility
Volatility is the magnitude and speed of price fluctuations in a stock or market index. Higher volatility indicates larger price swings and faster changes; lower volatility indicates stability. Volatility is measured using standard deviation or the VIX index.
Formula
Annualized Volatility = Standard Deviation of Daily Returns × √252
For example, if daily returns have standard deviation of 2%, annualized volatility = 2% × √252 ≈ 31.7%.
Example
Tesla (TSLA might have annual volatility of 50-70%, meaning daily moves of ±2-3% are common. The S&P 500 (SPY might have volatility of 15-20%, with daily moves of ±0.5-1%. Treasury bonds have volatility of 5-10%, reflecting their stability.
How to Interpret It
- High volatility (> 30%): Stock or market is moving rapidly. Traders love volatility; long-term investors may find it stressful.
- Low volatility (< 15%): Stable, predictable price movements. Common for mature, blue-chip stocks and bonds.
- Rising volatility: Often signals market uncertainty, fear (VIX spike), or news events.
- Falling volatility: Usually signals confidence, calm markets, bullish environment.
- Sector volatility: Tech and biotech are naturally more volatile than utilities or consumer staples.
Limitations
- Volatility is backward-looking; historical volatility doesn't predict future volatility.
- Volatility varies based on time frame; daily volatility differs from monthly or annual volatility.
- Implied volatility (VIX) measures market expectations of future volatility; it can diverge from realized volatility.
- High volatility offers both risk and opportunity; large losses are possible, but so are large gains.