Back test and verify any mix and match of stocks, ETF-s, CEF-s and mutual funds listed on Yahoo Finance over several months/years. This software will let you graphically visualize and compare results to the major index S&P500. Play with different allocation sets, increase and reduce risk at will. Try different reallocation schemes to compare potential results.

Major institutions use complex programming tools based on huge and expensive databases to experiment with portfolio construction. Now, at your fingerprints and for free - a tool as easy as it´s name: EzBacktest.