The iSTOXX American Century USA Quality Growth Index aims at investing in high-growth companies as well as in companies with sustainable growth prospects and attractive valuations. The index concept allocates dynamically to both a high- and a stable-growth strategy. The allocation of the strategies is governed by a risk-adjusted momentum signal. The high-growth strategy is represented by the iSTOXX® A.C.I. USA Pure Growth Index; the stable-growth strategy is represented by the iSTOXX® A.C.I. USA Stable Growth Index.