Hedge fund manager William Ackman told investors that his publicly traded portfolio has gained 24.7 percent this year, fueled by strong growth in Fannie Mae, Freddie Mac and Chipotle Mexican Grill stocks. BOSTON: Hedge fund manager William Ackman told investors that his publicly traded portfolio has gained 24.7 percent this year, fueled by strong growth in Fannie Mae, Freddie Mac and Chipotle Mexican Grill stocks.