QLD is a leveraged product and not a buy-and-hold ETF. The fund should only be used as a short-term tactical instrument. Like many leveraged funds, it delivers 2x exposure only over a one-day holding period. QLD should not be expected to provide index leverage returns greater than a one-day period. Over longer periods, returns can vary significantly from 2x the NASDAQ-100, a quirky but popular index dominated by technology stocks. As such, QLDs fate is closely tied to the technology market and, consequently, its a poor proxy for the broader US large-cap market. The underlying index is rebalanced quarterly and reconstituted semi-annually.