Ins and outs of ETF benchmarks

Article Excerpt

ETF managers use benchmark indexes to manage their ETF portfolios. Benchmarks are expected to fairly represent a target universe. The S&P 500 index, for example, is often used by ETF providers who aim to offer investors broad exposure to the U.S. stock market. Benchmark providers, such as Standard & Poor’s or the Financial Times, must decide which companies to include in a benchmark index and the weight to give each company. Most common is a market capitalization-weighted method where the market value of every stock is expressed as a percentage of the market value of all the stocks in the index. The problem with market capitalization-weighted indexes is that a few large companies can dominate the index. Another method for constructing indexes is the equal weighted method where every stock gets the same weight in the index. Note that can minimize the positive impact of top performers. With the proliferation of ETFs, the benchmark providers have created numerous variations of the traditional benchmark…