and Beverages Sector" alone accounts to 32 companies at a market capitalization of US$897.5 million. Studies show that in 2008 about 30 firms, involved in 11 industries, hold close to 75% of shares in Tehran Stock Exchange. 2009: A comparison of the top 100 Iranian companies and the Fortune 500 in 2009 indicated that the gross profit margins of the top 100 Iranian companies were almost double those of the Fortune 500. For Fortune 500 companies, the average gross profit margin was 6.9% and for the Iranian companies, it was 13%. The sector with the highest profit margin among the top 100 Iranian companies in 2009 is mining, with a margin of 58%. The mining companies in the Fortune 500 had a gross profit margin of 11%. After mining, other industries with highest margins are base metals, and telecommunications. 2011: The best performing industries in 2011, in terms of total sales, were the banking and automotive sectors. The worst performers were home appliances and electronics. In terms of gross profit margin, mining, telecommunications, and oil and gas exploration & production were the best performing industries. Sales totals of the top 100 Iranian companies on the list ranged from $12.8 billion or the top ranking company, Iran Khodro, to $318 million for the 100th company. 2012: Companies showing the most profit, are mostly in pharmaceutical, petrochemical and steel businesses. The sharp decline of the Rial in 2012 has made exports more competitive. Other favoured companies are state-owned industrial companies that rely on a mostly domestic supply chain, turning locally produced raw materials into products targeting Iranian consumers. 2015: Fluctuations in global prices of commodities and the official exchange rate of the Iranian currency have a big impact on the profitability of companies which produce global commodities that are either exported or sold on the free market domestically. More than half the weight of the Iranian stock market cap belongs to such companies. Market participants The Government of Iran directly holds 35 percent of the TSE, while securing another 40 percent through pension funds and investment companies such as the Social Security Investment Company, one of the largest institutional investors on the TSE. Bonyads also play a significant role in TSE trading. In 2016, TSE had 38,000 institutional investors. In 2005 fewer than 5 percent of Iranians owned stock. The Government is promoting the shareholding culture in Iran. By March 2010, 3.219