Berkshire Hathaway, which wrapped up its final year under Warren Buffett’s leadership, reported Saturday that operating earnings for the fourth quarter totaled $10.2 billion, down 29.8% from last year, on weakness from its insurance business.Berkshire Hathaway, which wrapped up its final year under Warren Buffett’s leadership, reported Saturday that operating earnings for the fourth quarter totaled $10.2 billion, down 29.8% from last year, on weakness from its insurance business.