????The California Public Employees Retirement System (CalPERS) has the nation's largest private equity portfolio, and recently updated fund-by-fund performance data on its website. These are the numbers by which PE investors really are judged, so I figured it was worth a quick look to see the five best -- and five worst -- performing funds within the CalPERS portfolio.

????Because private equity is a long-term asset class characterized by J-curvature, I've excluded all funds raised between 2007 and 2010. The relevant metric is net IRR. All data is through March 31. Here goes:

????THE BEST:

????1. Clearstone Venture Partners 1-B (1999): 154.7%

????2. T3 Partners II (2001): 95.6%

????3. GCP California Fund (2003): 91.9%

????4. WLR Recovery Fund II (2002): 79.5%

????5. Permira Europe I (1997): 74.5%

????THE WORST

????1. Aberdare II Annex Fund (2006): -46.6%

????2. Exxel Capital Partners V (1998): -41.7%

????3. Opportunity Capital Partners IV: -28.9%

????4. Convergence Ventures II (1999): -28.5%

????5. Richardson Capital Private Equity 2 (2006): -28.1%