What is Volatility?

Volatility refers to the degree of variation in the price of a financial instrument over time. It is a key indicator of the risk and uncertainty associated with the price movement of securities, such as stocks, bonds, or mutual funds. Higher volatility indicates larger price swings, while lower volatility suggests more stable prices. 

Types of Volatility 

Understanding the different types of volatility helps investors predict potential price movements and manage risk effectively. 
 

Historical Volatility: 

 

• Measures past price fluctuations of security. 
• Used to predict future price movements based on historical trends. 
• Does not indicate the future direction of the security's price, only the extent of past changes. 

Implied Volatility: 

 

• Reflects the market's expectations of future price movements. 
• Key factor in pricing options contracts, indicating how much the market believes a stock will fluctuate. 
• Helps traders gauge market sentiment and potential price volatility before the option expires. 

How to Calculate Volatility 

The simplest method to calculate implied volatility is by determining the standard deviation of a security's prices over a specific period. Here is how: 

1. Collect historical prices of the security. 
2. Determine the mean of these prices. 
3. Subtract the average price from each price. 
4. Square each difference to eliminate negative values. 
5. Add these squared differences together. 
6. Divide the sum by the total number of prices. 
7. Take the square root of the variance to get the volatility. 

Sample Calculation: 

To find the volatility of the stock of XYZ Corp for the past four days, with prices as follows: 

Day 1: ₹50 

Day 2: ₹55 

Day 3: ₹48 

Day 4: ₹58 
 

Average price:  

[(₹50 + ₹55 + ₹48 + ₹58) / 4] = ₹52.75  
 

Differences from the average: 

  - Day 1: (50 - 52.75) = -2.75  

  - Day 2: (55 - 52.75) = 2.25  

  - Day 3: (48 - 52.75) = -4.75  

  - Day 4: (58 - 52.75) = 5.25  
 

Squared differences: 

  - Day 1:  (-2.75)^2 = 7.56  

  - Day 2:  (2.25)^2 = 5.06  

  - Day 3: (-4.75)^2 = 22.56  

  - Day 4: (5.25)^2 = 27.56 
 

Sum of squared differences: 

7.56 + 5.06 + 22.56 + 27.56 = 62.74 
 

Variance: 

62.74 / 4 = 15.685 
 

Standard deviation: 

√15.685 = 3.96  

This indicates that the stock price of XYZ Corp usually deviates from its average stock price by ₹3.96. 
 

How Much Market Volatility Is Normal? 

Market volatility is inherent to investing and varies over time. On average, investors can expect around 15% volatility from average returns annually. Most of the time, the stock market is relatively calm, with brief periods of significant price movements.  

Bullish markets, characterised by rising prices, tend to exhibit lower volatility compared to bearish markets, which often experience unpredictable price swings and increased volatility. Understanding and preparing for these fluctuations can help investors manage their portfolios effectively.