The total net profits of China's securities brokerages plunged 16.4 percent year on year in 2012 partly due to the country's lackluster stock market, new data has indicated.

According to the unaudited financial reports of 116 brokerage firms, their total net profits stood at 32.93 billion yuan (5.25 billion U.S. dollars) last year, the Securities Association of China said in a statement posted on its website on Wednesday.

Last year, 99 of these brokerages made profits, accounting for 86.84 percent of the total, the statement said.

Total revenue of those firms dropped 4.77 percent from a year earlier to 129.47 billion yuan, it added.

The sharp decline in profits is partly due to the weak performance of China's stock market in 2012, as the benchmark Shanghai Composite Index hovered at a low level and rose only 3.17 percent over the year.