US STOCKS-Wall St set to open lower after three-day rally
* All three major indexes on track to end week higher
* Twitter falls after brokerage downgrade
* Futures down: Dow 17 pts, S&P 3.5 pts, Nasdaq 8.75 pts (Adds details, comment, updates prices)
By Tanya Agrawal
Sept 23 (Reuters) - Wall Street looked set to open slightly lower on Friday as oil prices came off a two-week high, a day after the Nasdaq closed at a record high for the second straight day.
All three major indexes are poised to end the week higher after the S&P 500 index notched its best two-day performance in more than two months on Thursday. The S&P is up 6.5 percent for the year.
Investors have been in risk-on mode again, encouraged by the Federal Reserve's decision to stand pat on interest rates at a meeting this week.
"There is some consolidation after the very active and positive week for stocks based on news flow from the central banks, said David Donabedian, chief investment officer of Atlantic Trust Private Wealth Management.
Fed Chair Janet Yellen said on Wednesday that U.S. growth was looking stronger and rate increases would be needed to keep the economy from overheating and fueling high inflation. But the central bank maintained the low-interest rate environment that has helped underpin the bull market for stocks. Continuación...