EFTA Document EFTA01393180

markets are in various countries. A stock index may be based on the prices of all, or only a sample. of the securi- ties whose prices it is intended to represent. Like stock indexes. variability indexes, strategy-based indexes, and dividend indexes are securities indexes. However, varia- bility indexes may measure the implied volatility of an index, using the premiums for series of options on that index, or may measure the historical variance or volatility of the returns of an index using