Federal Reserve members engaged in heated debate in September before ultimately deciding not to ease back on their monthly bond-buying program, according to the minutes from the latest Fed meeting.
The sheer 12-page length of the document reflected a depth of discussion that focused on whether the economy was strong enough to wind down the buying, as well as whether the Fed was being as clear as it should be with its policy statements.
"All members but one judged that it would be appropriate for the Committee to await more evidence that progress would be sustained before adjusting the pace of asset purchases," the minutes said.
The decision to begin pulling back on the $85 billion a month in purchases of Treasurys and mortgage-backed securities was "a relatively close call" for "several members" who were concerned that financial markets had come to expect an unwinding, or tapering.
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Fed Chairman Ben Bernanke had been indicating since May that the central bank was ready to start the tapering process of quantitative easing.
Interest rates crested higher over the summer and equity markets were volatile.
Bernanke, though, had stressed that a decision was dependent on growth, and the economic signals were mixed at best.
"During the exchange of views on whether to trim the flow of asset purchases at this meeting, a number of members emphasized the contingent and data-dependent nature of the Committee's purchase program," the minutes state.
"In light of the mixed data recently, including inflation readings that remained below the Committee's longer-run objective, and the concerns over near-term fiscal uncertainties, some members indicated that they preferred to await more evidence that their expectation of continuing improvement would be realized.
Markets reacted little to the peek behind the scenes of the Fed's deliberations, with stocks mixed but mostly higher and bond yields ticking up as well.
"The Fed believes two things: they still think QE works and they're definitely afraid of pulling back too early," Peter Boockvar, chief market analyst at The Lindsey Group, told CNBC. "My answer to that is QE does not work in influencing the economy and it will not ever be a good time to remove QE because interest rates will head higher when that happens."
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In addition to three rounds of quantitative easing and another round of buying and selling an equal amount of bonds—known as Operation Twist—the Fed has kept its policy rate near zero.
It has set a 6.5 percent unemployment rate and 2.5 percent inflation as barriers before it will begin raising its rate; both metrics are well off those targets.
Esther George was the sole Fed Open Markets Committee member to vote against the QE decision, reasoning that economic progress was "sufficiently positive" to taper.
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