Key Points Costco outperformed the S&P 500 over the last 10 years by a wide margin. Much of the stock's previous 10-year return was due to an increase in the price-to-earnings multiple. 10 stocks we like better than Costco Wholesale › Costco Wholesale (NASDAQ: COST) has been a rewarding investment for investors. It would have made early investors millionaires, but even if you had bought the stock in 2015, you would still be outperforming the S&P 500. A $1,000 investment in Costco stock 10 years ag ...