HOWTO Beat the stock market: buy customer service

A study in the Journal of Marketing concludes that you can beat the market consistently by buying stock in companies with high customer satisfaction ratings:

Using a back-tested paper portfolio and an actual case, the study's authors found that companies at the top 20% of the the American Customer Satisfaction Index (ACSI) outperformed the the stock market, generating a 40% return. Over time, the portfolio outperformed the Dow Jones Industrial Average by 93%, the S&P 500 by 201%, and NASDAQ by 335%.

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