A stock exchange poll has found that investors' trading frequency plunged last year, with the average punter making three transactions last year against 10 in 1997. The phone survey of 2,154 adults last month aimed to ascertain the percentage of retail investors' participating in the market. It revealed 16 per cent of Hong Kong adults held or had traded shares last year, while 13 per cent had held on to their shares. The survey concluded a typical stock market retail investor was a 40-year-old white-collar worker with secondary or higher education and a monthly income of about $17,500. The survey found investors were generally well-educated and were professionals. It also found a growing number of female investors, such as housewives, white-collar and blue-collar workers, had been participating in the market in the past decade. A full-scale exchange survey on investors' trading patterns, carried out every three years, is due next year.