Warren Buffett, the 95-year-old CEO of Berkshire Hathaway, announced Monday in a letter to shareholders that he will be "going quiet" soon, invoking a Britishism to describe his plan for stepping down at the end of the year. And Buffett said he'll end his decades-long tradition of penning annual letters to shareholders. However, he isn't disappearing entirely. Buffett plans to continue sharing a yearly Thanksgiving message and, notably, indicated he will accelerate his philanthropic efforts, aiming to give away his entire $149 billion stake in the company, CNN reports. Buffett, whose folksy wisdom and investment savvy have made him a financial icon, revealed he recently converted $1.35 billion worth of Berkshire shares into the company's lower-priced "B shares" and distributed them to his children's philanthropic foundations.