Chairman Dan Wiener spoke with CNBC’s Bob Pisani about recent performance of some of the most heavily shorted ETFsA type of security which allows investors to indirectly invest in an underlying basket of financial instruments (these may include stocks, bonds, commodities or other types of instruments). Shares in an ETF are publicly traded on an exchange, and the price of an ETF’s shares will fluctuate throughout the trading day (traditional mutual funds trade only once a day). For example, one popular ETF tracks the companies in the S&P 500, so buying a share of the ETF gets an investor exposure to all 500 companies in the index.: SPDR Retail, VanEck Semiconductors and SPDR Oil & Gas E&P. Dan noted that trading volume remains relatively low with traders acting relatively bullish despite the markets being at or near record highs.