Five years to the week after the financial crisis reached its darkest moments, the Federal Reserve is expected to take the first step toward normalizing its monetary policy.

Chairman Ben Bernanke is expected to announce that the central bank will begin tapering the size of its monthly asset purchases in his scheduled press conference Wednesday afternoon.

Fed officials have insisted that the exact timeline for scaling down the monthly bond purchases will depend on the incoming economic data, and recent weaker-than-expected reports on employment and other statistics have cast some doubt on whether the Fed will go through with the taper at this week’s two-day meeting.

It’s possible that Bernanke and company will instead wait until a later month, and to continue adding stimulus to the economy in the meantime. Some Fed watchers have also suggested the meeting may result in only a very slight reduction in the size of the monthly bond purchases, or a simultaneous announcement that the Fed will keep rates lower for longer -- in recent announcements it has said that it will keep short-term interest rates near zero until unemployment falls below 6.5 percent.

Either way, this week is likely to see the Fed’s first step toward ending the historic quantitative easing programs that it launched in 2008 after its normal monetary policy tool, manipulation of short-term interest rates, became ineffective when rates fell to zero and stayed there.

This week five years ago top economic policymakers, including Bernanke, were dealing with the aftermath of the investment bank Lehman Bros. and trying to contain the fallout of the crisis. It was the week in which the Fed began experimenting with programs to extend credit to banks and in which Treasury Secretary Hank Paulson asked Congress to pass legislation to enable the Treasury to buy troubled assets -- the idea that would eventually become the law known as TARP.

President Obama plans to mark the occasion with a speech from the Rose Garden Monday morning. The president, who faces a still-weak labor market and high disapproval ratings for his economic management, is expected to defend his administration’s efforts to counteract the recession and assign blame to Republicans for holding up parts of his agenda.

Meanwhile, the search for Bernanke’s successor took a major turn over the weekend, when the candidate thought to be Obama’s favorite, the controversial Harvard professor and former Obama economic adviser Larry Summers, withdrew his name from consideration after a long and unusually high-profile and visible whispering campaign for the post.

Janet Yellen, the vice chair of the Fed, is widely thought to be the top remaining candidate. But the president has not shown a keen interest in appointing Yellen, and some Fed watchers have suggested that Summers’ withdrawal makes it unlikely that the president will choose Yellen, as she had become the de facto opposition candidate to Obama’s preferred candidate. A dark horse candidate could emerge in the coming days or weeks.

On Capitol Hill, the major event this week will be the House of Representative’s efforts to move a bill to fund the government. The government faces the prospect of a shutdown at the end of the fiscal year on Sept. 30 if Republicans and Democrats led by Obama cannot reach an agreement about spending levels. House Majority Leader Eric Cantor has indicated that the House might consider a bill this week after putting it off last week.

The Bureau of Labor Statistics will report on Consumer Price Index inflation for August on Tuesday morning. And on Thursday morning the National Association of Realtors will release data on existing home sales for August, after reporting a jump in sales in July.