The Exchange shall, save in exceptional circumstances, suspend from trading on the Exchange baskets which have one or more of their underlying securities suspended from trading in the market or exchanges on which such suspended security or securities are listed and the value or aggregate value of such suspended security or securities represents 30 per cent ("Specified Percentage") or more of the total value of all securities comprised in the basket, or such other Specified Percentage as announced by the Exchange from time to time. The value of the suspended security or securities shall be determined by reference to the price of such securities immediately prior to their suspension on the market or exchanges in which they are listed.