AMEX Biotechnology HOLDERS (IBH) is a per share estimate of the value of the securities underlying one share of Biotech HOLDRS, which trade on the Amex under the symbol BBH. The IBH Index is calculated based on the securities underlying a round lot of Biotech HOLDRS, adjusted to reflect the value for one share of BBH. The IBH Index originally included 20 companies that are involved in various segments of the biotechnology Industry.