Warren Buffett's Berkshire Hathaway (BRK.B) boasts a record so good that it's made him one of the world's wealthiest people, with a $150 billion net worth. Since 1965, Berkshire Hathaway has produced a staggering compounded annual return of 19.

Before announcing his plan to step down as Berkshire Hathaway chief executive at the end of the year, Warren Buffett offered a fervent defense of trade on Saturday, saying tariffs should not be a "weapon" and the United States would be better off if other countries shared its prosperity.

Warren Buffett is a smart investor. He's been investing since age 11 (in 1942), and has always been one to pay attention to macroeconomics and the stock market. Read More: Warren Buffett's Top 4