The Bank of England's quantitative easing (QE) programme is putting a stop to the five-month ascendency of the pound.Although sterling climbed 23.5 per cent between March 10th and August 5th - the largest five-month rally seen in 24 years - it has been steadily losing ground since then, when the Bank announced the extended QE programme.Only three of the 176 currencies tracked by Bloomberg posted a worse performance during this period.Hans-Guenter Redeker, the London-based global head of foreign-exchange strategy for BNP, told the news agency: "I'm super-bearish on the pound. The Bank of England has made it clear it can't afford a stronger currency."As well as extending QE by £50 billion to £175 billion - exceeding the £150 billion barrier set by the Treasury - the Bank's Monetary Policy Committee also voted to keep interest rates on hold at 0.5 per cent, the lowest the base rate has been the 315-year history of the bank.