U.S. stock index futures fell early on Friday, as the rocky ride in global markets continued.
a spokesman for the brokerage firm said without elaborating on the cause.
Dow Jones industrial average futures declined more than 150 points and trimmed losses to briefly trade less than 100 points lower, after showed an increase of 0.4 percent in personal income and an increase of 0.3 consumer spending.
Bond yields edged lower after the 8:30 a.m., ET, data release. The U.S. 10-year Treasury note yield traded near 2.14 percent, while the 2-year yield was 0.68 percent.
Personal income and spending is the Federal Reserve's preferred measure of inflation. June consumption was revised slightly higher to 0.3 percent from 0.2 percent.
The major averages closed Thursday more than 2 percent higher.
With gains on Wednesday and Thursday, the S&P had its best two days since March 2009 and the Dow had its best two days since December 2008, according to Howard Silverblatt of S&P Dow Jones Indices. Still, he noted the S&P 500 has lost $1.02 trillion in the last eight days.
On Friday, the benchmark Shanghai Composite index ended 4.8 percent higher, after an exceptionally volatile weak for Chinese stocks. The index closed down 7.8 percent on the week. European trade was cautious on Friday with markets narrowly lower as investors remained cautious.
The final read on August consumer confidence from the University of Michigan at 10 a.m., ET, takes particular prominence. In comments Wednesday, New York Fed President William Dudley singled out the index as an indicator of the volatile stock market's impact on the economy.
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Dudley said the case for a September rate hike has become less compelling. Central bank policymakers also continue their annual meeting in Jackson Hole, Wyoming, on Friday.
No major earnings are expected on Friday.