The oil company Saudi Aramco surpasses, in value, any profile company in the world listed on the stock exchange. With a market capitalization of $ 1.8 trillion, the Saudi state-owned giant is worth more than the next five largest listed oil and gas companies combined, including Exxon Mobil, Chevron, Shell and PetroChina, according to an analysis by visualcapitalist.com. The cited source ranks the 20 most valuable oil and gas companies in the world by market capitalization, using data from