The FSA has been forced to admit it lost dozens of staff in the third quarter alone, after Lord Myners questioned the Treasury about a flurry of recent exits from the regulator.
Labour Lord Myners asked the government how many FSA employees resigned in the three months to the end of October, according to official records.
In a response dated 25 November, Tory Lord Sassoon, commercial secretary to the Treasury, produced a table showing the regulator received 96 resignations from staff in the period.
Voluntary exits for August were 35, with 27 leaving in September and a further 34 last month.
The FSA's annual staff turnover as at the end of October was 9.5%, because in that month 77 people accepted jobs with the FSA.
"The management and board of the FSA consider turnover rates of up to the financial services industry norm of 15% to be manageable.
"The FSA remains confident it can continue to staff effectively the FSA at its projected headcount of 4,000 full-time equivalents, " he told Myners.
Sassoon said the intention is to cap the FSA's headcount at the current level until the transition to the new bodies of the Consumer Protection and Markets Agency and the Prudential Regulatory Authority in 2012.
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