62% to R17.25 lakh crore till July 15 of the current fiscal because of poor trading volumes in almost all commodities, the Forward Markets Commission said on Wednesday.
The business at these exchanges stood at R45.53 lakh crore in the same period of the last financial year, the regulator said in a statement.
Maximum fall in the turnover was seen in bullion followed by energy, metals and agricultural commodities.
According to data from the Forward Markets Commission, the turnover from bullion fell by over 70% to R6,18,569 crore during April and July 15 of the 2014-15 financial year, from R20,95,113 crore in the year-ago period.
Similarly, the business from metals declined by 68% to R3,69,946 crore from 11,65,626 crore, while the turnover from metals like copper fell by 57% to R3,72,367 crore from R8,70,273 crore in the review period.
Turnover from agricultural commodities also fell by over 14% to R3,64,574 crore from R4,22,890 crore in the same period.
The turnover of the commodity exchanges has been declining since the imposition of commodity transaction tax.
Investors' confidence has also come down in futures trading after the R5,600 crore payment crisis at the National Spot Exchange Ltd (NSEL), analysts said.
There are five national and six regional exchanges in the country.