How Stocks Work Full Size Version Share | Have A Question About This Topic? Name Email Address Question Thank you! Oops! Related Contents Investments You’ve made investments your whole life. Work with us to help make the most of them. The Anatomy of an Index The S&P 500 represents a large portion of the value of the U.S. equity market, it may be worth understanding. What Is the Dividend Yield? This calculator helps determine your pre-tax and after-tax dividend yield on a particular stock.