ETF of the Week: Vanguard S&P Small-Cap 600 Value ETF (VIOV) ETF Trends CEO Tom Lydon discussed the VIOV seeks to replicate a benchmark that offers exposure to small cap firms that exhibit value characteristics in the U.S. equity market. The investment thesis behind small caps is that these firms are likely to provide strong growth prospects to a portfolio and should have a much easier time growing then their large cap counterparts. However, these securities are extremely volatile and can experience large losses or gains in a concise period of time. Despite their volatility, these products should probably be in every investors’ portfolio. They tend to move somewhat independently of large caps and can be a better pure play’ on the American economy.