Companies that have bought back their shares have outperformed net issuers of equity by an average of 10% a year since 1989, according to Lehman Brothers.

However, performance has varied over time. Net buyback companies outperformed net issuers by 19.9% a year between March 1994 and September 1999 and by 28.3% a year between August 2000 and May 2003. Since April 2004, they have outperformed by 43.8%.