The simplest way to do it is to calculate the standard deviation and best non-technical illustration of the same is from Subra:
Rahul Dravid’s individual score will typically be close to his average – Low standard deviation. Example, debt mutual funds
Virender Sehwag’s individual score can just about be anything! High standard deviation.Example, gold, stocks, equity mutual funds.
Here is a 3-minute video on what the standard deviation is and how it can be used to measure risk associated with an equity investment.
I strongly believe that understanding standard deviation is the key to successful mutual fund investing.
It is a fantastic way to select mutual fund categories suitable for your financial goals
Although useful to get a sense of volatility, the standard deviation is too simplistic to make predictions. So one should use it with care/caution.
I have written several posts about standard deviation. Here are a few:
Here are two screenshots of the performance tab at Value Research: standard deviation and average monthly return over the last 3Y are listed here.
The risk & rating tab at MorningStar where the standard deviation is listed along with the CAGR.
Higher the standard deviation, higher the volatility. This is reason why Gold is riskier than Stocks!