Federal Reserve policymakers last month indicated that interest-rate decisions could become less predictable, relying more heavily on short-term economic prospects than on more sweeping monetary strategy.
Minutes of the Fed's closed-door meeting on Jan. 31 - chairman Alan Greenspan's last - were released Tuesday and offered insight into policymakers' thinking as they contemplated what might be the appropriate end point in the Fed's nearly two-year credit tightening campaign and as they prepared for the new chief, Ben Bernanke.
"Although the stance of policy seemed close to where it needed to be given the current outlook, some future policy firming might be needed" to keep inflation and the economy on an even keel, according to the minutes.
One of the first challenges facing Bernanke, whose first day on the job was Feb. 1, will be to work with his Fed colleagues and decide when to stop boosting rates. If he stops too soon, inflation could get out of hand. If he waits too long, the economy could be hurt.
Bernanke's first interest-rate meeting is March 27-28. In congressional testimony last week, he hinted another rate increase could come at that time to help keep inflation in check.
At the January meeting, the Federal Reserve boosted a key interest rate, called the federal funds rate, by one-quarter percentage point to 4.50 percent, the highest in nearly five years. That was the 14th increase of that size since the Fed began to tighten credit in June 2004.
The funds rate, the interest that banks charge each other on overnight loans, is the Fed's main tool for influencing economic activity.
In the future, though, the path of interest rates might not be nearly as predictable as it had been, Fed policymakers indicated in the minutes.
"All members agreed that the future path for the funds rate would depend increasingly on economic developments and could no longer be prejudged with the previous degree of confidence," the minutes stated.
The rate increase in January was part of a long-term process in which the Fed strategy was focused on lifting rates from historically low levels to more normal ones.
Before the Fed embarked on its rate-raising campaign, the funds rate had been sliced to 1 percent, a 46-year-low, in an effort to help the economy get back on its feet after the 2001 recession, terror attacks and a wave of accounting scandals that rocked Wall Street.
"They are definitely off autopilot," said Lynn Reaser, chief economist at Bank of America's Investment Strategies Group. "Although another increase at the end of March seems likely, the statement in the minutes reinforces the view that future policy steps will depend more on the behavior of economic statistics."
On Wall Street, stocks dropped as the Fed minutes and other economic information cemented investors' feelings that more rate increases are a near certainty. The Dow Jones industrials lost 46.26 points to close at 11,069.06.
At the January meeting, policymakers thought the economic slowdown seen in the final quarter of 2005, where gross domestic product expanded at a feeble 1.1 percent pace, was probably in part because of "transitory factors" and they predicted that growth would bounce back this quarter.
To that end, economic barometers on factory production, job creation and business demand pointed to improving economic activity, according to the minutes.
That was consistent with the economic assessment Bernanke offered Congress last week.
The economy "would expand at a fairly robust pace of the first half of this year, boosted in part by spending on recovery activities associated with the (Gulf Coast) hurricanes," the minutes stated. After that, growth was expected to moderate, mostly reflecting the effect of a slowing housing market.
The housing boom over the past five years in particular has been an important ingredient in consumer spending and economic activity. Rapidly rising house prices have made homeowners feel wealthy and thus inclined to spend.
While a sharp slowdown in housing would spell trouble for the economy, the Fed minutes suggested the most likely outcome was a gradual moderation. That was consistent with the message Bernanke delivered to lawmakers last week.