KARACHI (Reuters) - The cut-off yield on Pakistans benchmark six-month Treasury bills rose to 12.5517 per cent at an auction on Wednesday from 11.5151 per cent in an auction on July 15, the State Bank of Pakistan said. The weighted average yield on the six-month paper rose to 12.4425 per cent compared with 11.3847 per cent on July 15. The cut-off yield for the 12-month paper rose to 12.4442 per cent, compared with 12.2292 per cent in a previous auction on Aug. 12, while the weighted average yield rose to 12.4204 per cent, compared with 12.1620 per cent. The cut-off yield and weighted average yield for the three-month T-bills were 12.3792 per cent and 12.3603 per cent respectively. The central bank raised 43.25 billion rupees in the auction. The target was 60 billion rupees. This was the fourth T-bill auction for the 2009/10 fiscal year that began on July 1.