US STOCKS-Wall St posts worst week since June with Fed in mind
* Dow Jones industrial average breaks six-week streak of gains
* JC Penney's stock is S&P 500's biggest percentage decliner
* Priceline gains on results, near $1,000 a share
* BlackBerry open to going private, sources tell Reuters
* Dow down 0.5 pct, S&P 500 off 0.4 pct, Nasdaq off 0.3 pct
By Caroline Valetkevitch
NEW YORK, Aug 9 (Reuters) - U.S. stocks fell on Friday and posted their biggest weekly decline since June as investors focused on when the Federal Reserve would begin to scale back its stimulus.
All but one of the 10 S&P 500 sector indexes ended lower.
The stock of J.C. Penney Co. skidded 5.8 percent to $12.87 and ranked as the S&P 500's biggest percentage decliner. Bill Ackman, the company's top investor, urged the retailer's board on Friday to replace its chairman. Continued...