“Sotheby’s now lags behind the Standard & Poor’s 500 index after enriching investors for five straight years. It slipped as much as 8.8 percent today, compared with a 3.1 percent fall in the S&P 500, before both rebounded. For the year, Sotheby’s is down 22.4 percent, or more than twice as much as the S&P, which has lost 9.1 percent.”