The main gauge of Tehran Stock Exchange, TEDPIX, shed 8,405.83 points, or 0.7% to further retreat to 1,185,603.
The TSE's equal-weighted index was down 0.23%. The index gives the same weight to all shares, irrespective of their market cap.
Prices in 428 active tickers at TSE and the junior exchange Iran Fara Bourse declined, representing 80% of the total, according to Eghtesad News.
The value of shares put up for sale increased by 26% on Sunday compared with a day earlier to reach 55.85 trillion rials ($220 million).
With a remarkable decline in liquidity of shares, the value of retail trade declined by 28% for the day, the lowest in the current fiscal year that started in March 2020.
The low liquidity of shares is partly attributed to new price spread mechanism enforced by the stock market regulator since Feb. 13, based on which share prices spread from -2% to +6% a day instead of the previous ±5%.
The new daily price spread has helped prevent TEDPIX from a further collapse, as share prices can fall by maximum 2% per day.
TSE Trade
About 1.99 billion shares valued at 24.6 trillion rials ($98.42 million) changed hands at TSE for the day.
Iran Merinos Manufacturing Company was the biggest winner, as its shares went up 4.4% to 67,570 rials per share.
Sepahan Oil Company incurred the biggest loss among all TSE-listed companies and went down 2% to 14,700 rials per share.
Mobarakeh Steel Company gave the biggest push to the benchmark's fall, followed by Social Security Investment Company, Persian Gulf Petrochemical Industries Company and Golgohar Mining and Industrial Company.
Opal Kani Pars Mining and Processing Company gave the biggest boost to the benchmark index followed by Eghtesad Novin Bank, HiWeb Company and Soufian Cement Company.
IFB Down 0.4%
Iran Fara Bourse main index, IFX, lost 65.97 points or 0.39% to close Sunday trade at 16,920.5.
About 658.95 million securities valued at 72.21 trillion rials ($288.84 million) were traded at the junior exchange for the day.
Arya Sasol Polymer Company, Zagros Petrochemical Company, Saba Tamin Investment Company and Gohar Zamin Iron Ore Company had the most negative impact on IFX.
Ghadir Petrochemical Company gave the biggest boost to IFX followed by Marun Petrochemical Company, Chaharmahal Food Products and Sugar Company and Sobhan Oncology Pharmaceutical Company.