Quiz!
If you add annually to a portfolio that drops 50% in one year and recovers the next year, what penalty or benefit do you get when compared to a portfolio with the same returns (0%) and no volatility?
 50%
 No impact.
 +50%
How to Use Volatility to Make Money
Investment volatility is the investment’s movements up and down away from its average growth. It is commonly viewed as a negative, but for a disciplined longterm saver, it is typically a positive. A hypothetical example can demonstrate it. Let’s compare 2 portfolios with identical returns, and different volatility:
Portfolio 1 
Portfolio 2 

Year 1 
0% 
50% 
Year 2 
0% 
100% 
Average 
0% 
0% 
If you start with $100, both portfolios will be worth $100 after 2 years. Specifically, Portfolio 2 will go through the following values: (Year 1) $100 – 50% = $50. (Year 2) $50 + 100% = $100. The portfolios have identical average growth, but Portfolio 2 is far more volatile.
Let’s see the final balance if you add $100 in the beginning of each year:
Portfolio 1 
Portfolio 2 

Year 1 
($100 + 0%) = $100 
($100 – 50%) = $50 
Year 2 
($100 + $100) + 0% = $200 
($50 + $100) + 100% = $300 
Even though both portfolios have the same average growth, when adding to both portfolios identical amounts each year, the more volatile portfolio ended up 50% higher ($300 vs. $200).
How is this possible? The percentage going back up is greater than the original percentage going down. When a portfolio recovers from a 50% decline it goes up 100%. This is because the percentage going up is relative to a lower starting amount. While old money simply recovers, new money that was invested low goes up $100 – double the $50 impact of the decline.
Notes:
 Some investors lose faith in their portfolio after declines, and hold off on investing (or even sell). If you do that, you can negate the entire benefit of volatility and even hurt your returns.
 Even with discipline, there is a special case that can lead to a negative effect. The case involves no up period after a down period, for example, only up years followed by only down years. This is not a concern for disciplined lifelong investors, because such a sequence is limited to one cycle or less.
Quiz Answer:
If you add annually to a portfolio that drops 50% in one year and recovers the next year, what penalty or benefit do you get when compared to a portfolio with the same returns (0%) and no volatility?
 50%
 No impact.
 +50% [The Correct Answer]
Explanation: See this month’s article for an analysis of this scenario.
Disclosures Including Backtested Performance Data