No matter what investment discipline you use, there are three important variables for measuring your success — peak-to-valley drawdown, beta, reward/risk ratio. The first and most important factor is your measure of risk. Performance volatility is a measure of the variability of an investment’s rate of return.
Specifically, it is the standard deviation of the sample set of monthly returns that have been observed for the investment over the interval being considered. A simple way to measure a good stock market timing system is to calculate the largest peak-to-valley drawdown that has or would have occurred in the last five years. This drawdown is your measure of risk.
Second, is your beta to the overall market. Beta is an important variable that measures portfolio or timing system volatility as compared to an index. Most Betas are calculated based on the S&P 500 index. A beta of one tells you that the system has the same volatility (i.e. risk) as the S&P 500 index. A beta of two tells you that the system has twice the volatility as the S&P 500 index.
By actively managing your money, your stock market timing system should allow you to reduce the beta of your portfolio as compared to the index you are trading and substantially improve your returns over time.
Third, is your reward/risk ratio, which calculates your reward as compared to your risk. In order to calculate this, you need to know your average rate of return. A rule of thumb is that your return should be at least twice as large as your risk. For example, if your largest peak-to-valley drawdown percentage over the last five years is 15%, your average rate of return should be at least 30%. In other words, your reward/risk ratio (30%/15% = 2) should be 2 or greater.
The best stock market timing system for you will depend a lot on your personality, specifically your tolerance for risk. You might think a trend timing system that averages 80% is a great system, but what if I told you that system had a risk potential of 35%?
Most people cannot tolerate a system that decreases their investment capital more than 20%. Your tolerance and ability to accept risk should help you identify a stock market timing system that’s right for you.
There are only a few systems available that really work. Most come and go like mayflies on a warm summer’s day. When evaluating a timing system, it’s important to consider all of the above factors plus whether or not the system has survived and prospered over at least a five year period. If they’ve made it through the last five to six years, you’ve likely found a good stock market timing system.