Volatility
Volatility is how much and how quickly a share’s price moves up and down over a period, regardless of direction.
What it is
A share that moves 0.5% on a typical day has low volatility. One that regularly moves 4% has high volatility. Volatility says nothing about whether the price is going up or down, only how wide the swings are.
Small companies, companies in cyclical industries and shares going through big news usually have higher volatility. Large, steady businesses usually have lower volatility.
How to measure it
Traders use several tools. ATR (average true range) shows the average daily move in rupees. Bollinger Bands widen when volatility rises and narrow when it falls. Statisticians use the standard deviation of daily returns.
Volatility also changes over time. Quiet periods with narrow ranges are often followed by bigger moves, and wild periods often calm down. A Bollinger squeeze is one way to spot a quiet patch.
Why it matters
Volatility sets how much you can lose in a normal week. If a share regularly swings 5% in a day, a stop-loss placed 2% away will be hit by normal noise. You need a wider stop, which means a smaller position for the same rupee risk.
Higher volatility is not the same as higher return. It means higher uncertainty. Some volatile shares go up a lot; many simply swing around and wear down the people holding them.
Two shares, same price, different swings
Share A and share B both trade at ₹400. Over the past month A moved about ₹4 a day on average, and B about ₹20 a day. A ₹10 stop-loss would rarely be hit by normal moves in A, but B could hit it on an ordinary day. To risk ₹2,000 on each, you could buy 200 shares of A with a ₹10 stop, but only 50 shares of B with a ₹40 stop.
Common mistakes
- Confusing volatility with direction. A volatile share can go nowhere for months.
- Using the same stop-loss distance for calm and wild shares.
- Taking the same position size in a volatile small cap as in a steady large cap.
A share’s daily moves have doubled in size this month. What should a careful trader consider?
- A wider stop-loss and a smaller position to keep the same rupee risk
- A bigger position because more movement means more profit
- Nothing, since volatility does not affect risk
Show the answer
A wider stop-loss and a smaller position to keep the same rupee risk. Bigger swings mean normal noise can hit a tight stop. Widening the stop and cutting the size keeps the possible loss the same.
Common questions
Is high volatility good or bad?
Neither by itself. It means larger price swings and more uncertainty, which raises both risk and the chance of large moves either way.
How is volatility measured?
Common tools are ATR, Bollinger Band width and the standard deviation of daily returns. Each shows how wide the price swings have been.
What is India VIX?
It is an index from NSE that estimates how volatile the market expects NIFTY 50 to be in the near future, based on option prices. It is often called the fear index.
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