Hedge fund manager Bill Ackman appears to have scored one of his best years ever in 2020 despite a volatile market rocked by a global pandemic, an economic recession and a presidential election. His Pershing Square fund netted a 70.2% return last year after a 4.6% gain in December. That performance was far better than the 2020 return of the Dow Jones Industrial Average, S&P 500 or even the Nasdaq Composite, which posted a robust gain of 43.6%.