Berkshire has outperformed the S&P 500 during the past year and past three years, and has nearly tripled during the past five years while the S&P 500 has doubled. The gains come even as Berkshire has been reducing its investments in equity securities and building up its cash position.

There may never have been a smoother transition from an iconic CEO to a successor. Warren Buffett and Berkshire Hathaway ( BRK.A -0.46%) ( BRK.B 0.06%) let markets know several years ago that Greg Abel would be Buffett's eventual replacement. Abel is currently vice chairman of Berkshire's non-insurance businesses.

Berkshire Hathaway B shares slid 4.1% Monday afternoon, after Warren Buffett stunned shareholders on Saturday with the announcement that he plans to step down as CEO at the end of the year.