Comparing the Performance of Market Cap Stocks

Using three popular State Street "SPDR" (pronounced "spider") exchange-traded funds (ETFs), we can get a rough proxy for how different market caps have performed in recent years. These funds track different S&P indexes designed to represent large-, mid-, and small-cap stocks:

• SPY: The SPDR S&P 500 ETF
• MDY: The SPDR S&P MidCap 400 ETF
• SPSM: The SPDR Portfolio Small Cap ETF