The stock market opened sharply lower Thursday morning as the industry eagerly awaits Federal Reserve Chair Janet Yellen’s speech later in the day, in case she gives any clues on when the Federal Open Market Committee will raise interest rates. 

According to an article in Money Morning,Yellen will speak on inflation dynamics and monetary policy at 5:00 p.m. Eastern at the University of Massachusetts.

The S&P 500 is down 2.8% in the last five sessions and was off another 1.1% Thursday morning. Commodities have also tumbled. Copper, long a barometer of economic health thanks to affordability and numerous uses, is down 6% since last Thursday. Oil prices are down 5.6% since the FOMC meeting.

Last week, the Federal Reserve announced it would once again delay liftoff from its zero interest rate policy.

"To support continued progress toward maximum employment and price stability, the Committee today reaffirmed its view that the current 0 to 1/4% target range for the federal funds rate remains appropriate," read a statement from the FOMC at the time of the announcement. "In determining how long to maintain this target range, the Committee will assess progress—both realized and expected—toward its objectives of maximum employment and 2% inflation."