As shown, the S&P 400 Midcap Index closed down slightly in 2011, dropping about 1.73%. The annualized returns of the Index from 1992-2011 were about 10.96%, the 5-year annualized returns through 2011 were about 3.32%, the 10-year annualized returns through 2011 were about 7.04%, and the 15-year annualized returns were about 9.98%. The total returns (including reinvested dividends) between December 31, 1991 and December 31, 2011 were an impressive 699.85%.
As I have mentioned in previous years, I am a big fan of midcap stocks and recommend that any long-term investor seriously consider investing money in midcap stocks, such as those tracking the S&P 400 Midcap Index (e.g., the Midcap SPDR ETF (symbol: MDY) tracks the S&P 400 Midcap Index). Midcaps tend to provide higher returns over time than large cap stocks, such as those comprising the S&P 500 Index, although such stocks are generally more volatile over shorter time periods.
I have posted an updated chart for the period between 1992-2014.