The Borsa Istanbul 30 Index also referred to as BIST30 is a capitalization-weighted index of top 30 companies listed in the Istanbul Stock Exchange with the highest market value. Companies listed are from various sectors, the leading sector of the BIST30 is banking with 32.5%, leading companies are Garanti Bankasi A.S. with 10.69% volume and Akbank T.A.S. with only 0.68% behind the leader.