The dollar is slipping ahead of the Fed

The dollar is slightly weaker on Wednesday ahead of the Fed's decision.

The US dollar index is down by 0.2% at 101.54 as of 8:39 a.m. ET.

The latest interest rate decision from the Federal Reserve will be out at 2 p.m. ET.

Virtually everyone expects that the Fed will hike rates by 25 basis points. In fact, the World Interest Rate probability data provided by Bloomberg has traders seeing a 100% chance of a hike.

"A hike today is as nearly a foregone conclusion as these things can get," Marc Chandler, global head of currency strategy, wrote. "The idea of not wanting to surprise the market, which some Fed officials underscored, works both ways. It means the market expectations are primed. It also means that when there is a nearly 100% chance discounted, not to deliver would also be a destabilizing surprise."

Folks will likely be paying close attention to the Fed's dot plot for hints about future hikes.

As for the rest of the world, here's the scoreboard as of 8:47 a.m. ET:

• The British pound is up by 0.4% at 1.2194 against the dollar. Earlier, data released by the Office for National Statistics showed that the headline unemployment rate fell to 4.7%, a level last seen in the summer of 1975. However, real wage growth in the UK is slowing: regular pay rose by just 0.8% - the lowest rate since October 2014.
• The euro is higher by 0.2% at 1.0623 against the dollar as Europe gears up for the first of numerous important elections this year: the Dutch elections. The country's political landscape is fragmented, with over 28 parties in these elections, meaning that a coalition between two or more parties would be needed to form a majority government. Recent polls suggest that Geert Wilder's populist party has dipped in popularity, but even if his party were to win the popular vote, it is unlikely that he would become the next prime minister given that many of his rivals have ruled out forming a coalition with the PVV.
• The South African rand is stronger by 0.6% at 13.0724 per dollar after poor retail sales, which fell by 2.3% year-over-year in January, compared to forecasts of an uptick of 1.2%. "The fall in retail sales in January is disappointing given the improving picture painted by [Tuesday's] mining and manufacturing figures. Even so, we expect that growth will pick up later in the year as agricultural production rebounds and inflation eases," John Ashbourne, Africa economist at Capital Economics, wrote.
• The Russian ruble is up 0.2% at 59.0526 per dollar, while Brent crude oil, the international benchmark, is higher by 1.6% at $51.73 per barrel.
• The Japanese yen is little changed at 114.72 per dollar.