CS First Boston downgrades corporate startegy research company Corporate Executive Board (EXBD

) to neutral from outperform.

Analyst Gregory Cappelli says Corporate Executive Board has appreciated 20% year-to-date and now sits above his $73 target. He downgrades solely on valuation, as Corporate Executive Board now trades at 20 times his 2006 EBITDA estimate and 39 times earnings.

More importantly, he notes his Value Equation Framework indicates the stock is now embedding 14.5% long-term operating profit growth (3 to 5 years), which is in line with his expectations. He estimates a 2006 free cash flow yield of about 3%.

Capelli continues to believe Corporate Executive Board has one of best business models in his Global Services coverage universe. He sees 39 cents second-quarter earnings per share, $1.77 2005 earnings per share, and $2.06 2006 earnings per share.