US Federal Reserve Bank of St Louis President James Bullard, who has backed stimulus, said a small tapering of bond buying is possible next month after the Fed made a close call this week in deciding not to slow purchases.

“That was a borderline decision” after “weaker data came in,” Bullard said. “The committee came down on the side of, ‘Let’s wait.’”

Bullard called October a “live meeting,” because “it’s possible you could get some data that change the complexion of the outlook and could make the committee be comfortable with a small taper in October.”

The Fed this week unexpectedly refrained from reducing its $85 billion in monthly asset purchases, saying it needs to see more signs of sustained labour market gains.

Chairman Ben Bernanke said the central bank would decide on whether to taper purchases based on “what’s needed for the economy.”

The Fed will be able to weigh the September jobs report and revisions of prior months as well as updated housing reports at its 29-30 October meeting, Bullard said in a separate interview at Bloomberg’s headquarters in New York.

“This was a very close call so maybe the information would come in in a way that would change the complexion” of the outlook, he said.

Markets should not have been surprised by the decision because Federal Open Market Committee members have repeatedly said the decision to slow, or taper, would be “data dependent,” Bullard said.

“I’m a little dismayed at those in markets that are saying they’re surprised by this,” Bullard said.

The Fed said that, “if the economy was going to improve in the second half of the year, and if we saw that improvement, we would taper.”

Bernanke’s remarks earlier this year on the prospect for tapering sent bond yields as much as a percentage point higher.

Yields on the benchmark 10-year Treasury note climbed as high as 2.99% on 5 September from 1.93% on 21 May, the day before Bernanke first outlined a possible timetable for a reduction in the asset purchases.

This week’s FOMC decision not to taper helped reverse that rise and pushed back expectations for a tightening of monetary policy.

Investors see a 43% chance policy makers will increase the federal funds rate target to 0.5% or more by January 2015, based on data compiled by Bloomberg from futures contracts.

The odds were 68% two weeks ago.

“Rates went up a lot over the summer” and “for many on the committee that was a surprise,” Bullard said. It wasn’t a “surprise for me because I’ve said the flow of QE matters a lot.”

So “when we threatened to pull that back, markets naturally” sent yields higher, he said.

Bullard during the past two months has urged the Fed to hold off on adjusting so-called quantitative easing, saying any change should depend on whether inflation moves toward the Fed’s 2% target.