The basket will be composed of the stocks selected using criteria you entered, and the number of shares of each stock will be equal to the official index composition. For example, the Dow Jones index value is obtained by adding the stocks prices and multiplying by approximately 0.07374. If you elect to buy 10,000 shares of the index with true composition, TWS will propose to buy 737.4 shares of each stock (which it then rounds down to an even 700 shares).