SHANGHAI B shares rose in light trading as investors bought into companies which had posted solid interim earnings, said traders. The Credit Lyonnais Shanghai B Index rose 1.76 points, or 0.2 per cent, to 881.91 on turnover of just US$4.78 million. Bloomberg reported that 14 stocks rose, 10 fell and four were unchanged. The A-share index gained 156.37 points, or 4.32 per cent, on speculation that China might soon allow state pension funds to invest in the stock market. ''Pension funds would certainly bring a lot of money into stocks,'' said a Shanghai floor trader. With the interim earnings season about half complete, traders say the daily focus is on companies posting earnings. Shanghai Vacuum surged 8.2 per cent to 18.6 cents with 1.75 million shares changing hands, its most active trading day in several months. The company, one of China's largest black-and-white television tube makers, said yesterday its net profit for the six months to June 30 rose 50.5 per cent. ''Local investors don't care how a company makes its money, so they may have been buying today,'' said Hong Pui-leung, an analyst with Sassoon Securities. ''There may also have been some foreign investors who bought shares on the profit news without knowing the break-down,'' he said, referring to the company's revealing that a large proportion of its profits came from investment. Plush manufacturer Shanghai Haixin rose 1.1 per cent to 73 US cents after reporting a 78 per cent rise in first half net profits to 44.6 million yuan. ''On the back of the gradual pick-up of the US economy, Haixin is expected to capitalise on its downstream integration into the export-oriented toy-making companies,'' said Chris Fung, who covers the company for Sun Hung Kai Securities.