Futures traders, though, slashed their bets on September, dropping the chance from 19 percent to zero, according to the CME Group' s FedWatch tracker.

As things stand, it gives both the Fed two more months to weight the data on which it professes to be dependent for its next move, and for the markets to stress over what the Fed will do.

" It' s just 25 basis points and I think it' s important to put it into perspective," said Anika Khan, senior economist at Wells Fargo. " Of course the Fed will still be very much accommodative. If we look at the Fed' s balance sheet, that continues to be at an unprecedented high level and so that means the Fed is still going to be accommodative

The Fed had not raised interest rates in more than nine years and had been keeping its key funds rate near zero since late 2008, in an effort to breathe life back into an economy suffocated during the financial crisis and the accompanying Great Recession.

In addition to keeping rates low, it had instituted three rounds of quantitative easing, a monthly bond-buying program that pushed its balance sheet to $4.5 trillion and helped drive a 210 percent gain in the S& P 500 stock market index.

In the interim, the Fed had been looking for signs that the jobs market reached full employment and the economy was generating positive inflation. Though the inflation pace remains tepid, the unemployment rate has dropped to 5.3 percent and recently there have been signs of wage pressures.

Market participants do not expect a rate hike until December, with a 57 percent chance, up slightly from 55 percent prior to the Fed announcement.

The likelihood that the Fed would spring a surprise on the market appears remote to most observers.

" We' ve been at zero for so long. We' re just entering kind of a new phase and nobody' s sure how investors are going to react," said Carl Tannenbaum, chief economist for Northern Trust who formerly led a risk analysis team for the Fed. " If the Fed springs a surprise, then their chance of keeping things in good order are diminished."

There were no dissenters to Wednesday' s statement.