Alan Greenspan brought to an end is 18-years as chairman of the US Federal Reserve last by by presiding over a meeting that raised US interest rates for the 14th time in 19 months.
But the statement accompanying the decision to raise the official federal funds rate by another quarter-point to 4.5 per cent, the highest it has been since April 2001, indicated that the process may be coming to an end.
The Fed adjusted its guidance on future policy to leave the door open for Mr Greenspan's successor, Ben Bernanke, either to raise rates again or to call a halt.
The Fed said further rate increases "may" be needed, a shift from its guidance in December that higher rates were "likely."
A long-standing commitment to "measured" rises also vanished from the statement.
"Although recent economic data have been uneven, the expansion in economic activity appears solid," the Fed said.
"Core inflation has stayed relatively low in recent months and longer-term inflation expectations remain contained."
But the FED also repeated a warning that higher energy prices and tight labour markets "have the potential to add to inflation pressures."
Officials have said they expect the US economy to grow by about 3.5 per cent this year. But it expanded at an annual rate of only 1.1 per cent in the final three months of last year.
But another report this week showed consumer spending up by a sharp 0.9 per cent in December, with Americans dipping into savings. For 2005 as a whole, the savings rate fell to minus 0.5 per cent, the lowest since the Great Depression of the 1930s.