The major US, and well world indexes, for that matter, are all market capitalization-weighted indexes. This means the index will own a particular amount of one company or another based on that company’s market cap. On the surface, this sounds fine. And decades ago, when the indexes were really starting, this method worked just fine. It was a fast, easy, and simple way for investors and money managers to put together the index.
But fast forward to today and beyond, and market cap indexes may not be the best solution due to the simple issue of the index being too heavily weighted. In a past article, I highlighted how the top 5 companies in the S&P 500 represented 23% of the index. That means 5 companies represent almost a quarter of what an index that supposedly tracks 500 companies is doing.
However, over the past few years, especially the past year, these top five companies, Apple (AAPL), Microsoft (MSFT), Amazon.com (AMZN), Facebook (FB), and Alphabet (GOOG), have performed incredibly well. So, investors who have ridden these market-cap-weighted indexes higher for a few years are very happy and have done very well.
However, there is always a downside risk, and with these market-cap-weighted indexes being so heavily weighted to the top 5 or 10 stocks, the risk is much higher than most investors fully understand. Continue reading "Market-Cap-Weighted Investing Has Been Good, But Will It Last?"
