Has International Diversification Lowered Volatility?
One of the most basic questions of investing is what percentage of one’s assets should be invested in international stocks. Investing in international stocks has two potential advantages, lower volatility and higher long term returns, but neither is certain and the opposite could occur. Over the next couple posts we’ll look at both of these potential benefits, attempt to evaluate the risks and develop some heuristics for making wise asset allocation decisions. The idea that international diversification has lowered volatility is a central concept of Modern Portfolio Theory and is well supported by a number of studies. This is because, over the periods tested, although international markets underperformed the US stock market they tended to zig when the US zagged and therefore a combination of US and international stocks yielded a higher total return on investment with lower volatility. However, most of these studies focused on 30 or 40 year periods in the mid to late 20th c...