There's a new sheriff at the Federal Reserve and, on Tuesday, he is widely expected to give the green light to yet another hike in interest rates. The presumptive move, the 15th meeting in a row since the central bank started raising rates in June 2004, would take the Fed's key rate to 4.75%. But what happens after -- which the Fed will likely signal in its accompanying statement -- is anyone's guess. That's especially true after Friday's news of a plunge in new-home sales in February. The slowdown in housing, the motor of the U.S. economy over the past few years, has been monitored very closely to determine when the central bank will call it a day. "Bernanke has indicated that he and the Fed are looking at a broad array of indicators," says John Lonski, chief economist at Moody's Investors Service and a veteran Fed watcher. "But on balance, the data from housing will prove to be decisive." That also seemed to be the market's thinking as of Friday. While the market was pricing in 100% odds of a rate hike next week, odds of a move to 5% in May fell to 79% on Friday from 94% the previous day, according to Miller Tabak. The market still sees a 92% chance that the fed funds rate will stand at 5% at the June meeting, which implies a pause in May. Odds of a 5.25% funds rate in June dropped to 0% from 6%. It takes a while for a slowdown in the housing market to have a meaningful impact on the economy. But then again, Bernanke and the Fed probably don't want to fine-tune monetary policy too much, according to Lonski. "They don't want to repeat the mistake of Greenspan, who pushed rates to 6.5% in 2000 as clearly, that was a mistake," he says. "If they go to 5%, they can say 'we've achieved neutrality for now, let's see what happens.'"