PricewaterhouseCoopers (PwC) warned that if deal flow does not pick up, foreign investors could retreat from China's non-performing loan (NPL) market. PwC made the comment after conducting a survey of big players and finding them largely enthusiastic, with 17 banks saying they would invest up to US$15bn within three years. But in the three months since the survey, PwC has detected a change of heart, the firm telling the South China Morning Post: "Their optimism has turned to pessimism over the dearth of opportunities in the market." Only US$6bn in bank NPLs have been sold to foreign investors to date, nearly a third of that amount to only one investor, Citibank. One PwC official suggested investors could ending up looking more to Japan and Eastern Europe. Besides small deal flow, investors complain of an erratic approval, despite Beijing's effort to streamline the process. One sign of growing impatience among US investors came with Lone Star's decision to shutter its Beijing office in September