Mofid brokerage is the top provider of online trading services for Iranian stocks, Securities and Exchange News Agency (SENA) reported. The brokerage processed over 21% of all online trading in the first five months of the current Iranian year (March 20-August 21). The next three spots went to Farabi, Agah and Mobin brokerages each handling 3.7%, 3.4% and 3.2% of online trading traffic for the period. Online trading is steadily gaining traction in Iran. It made up 31% of all trading during the period. However, high transaction costs and system failures plague trading in Iran.