The market value of companies trading on the Borsa Istanbul stock exchange reached nearly TL 490 billion by the end of yesterday. On Monday, the market value of companies trading on Borsa Istanbul was approximately TL 488 billion. The most valuable company in the stock market is Garanti Bank with TL 26.418 billion, followed by Turkcell with TL 25.542 billion and Akbank with TL 23.680 billion.