This large- and mid-capitalization growth fund is managed with a long-term perspective, extremely low turnover, and a well-established investment strategy. Since the fund’s inception in 1984, PRIMECAP Management Company, the advisor, has followed an approach in which multiple portfolio managers independently manage a portion of the fund, which provides diversification of thought. One risk to note is that the fund may become concentrated in a few sectors, notably technology and health care. Short-term performance may be volatile when these sectors are strongly in or out of favor. This fund may be considered a complement to an already diversified portfolio with a long-term time horizon.