Nasdaq stocks posting largest percentage decreases

NEW YORK (AP) — A look at the 10 biggest percentage decliners on Nasdaq at the close of trading:

Questcor Pharmaceuticals Inc. fell 36.7 percent to $19.08.

BioFuel Energy fell 16.7 percent to $5.95.

Parametric Sound Corp. fell 13.1 percent to $7.75.

Veeco Instruments Inc. fell 10.2 percent to $31.40.

Vivus Inc. fell 9.7 percent to $18.96.

Facebook Inc. fell 9.1 percent to $20.79.

GT Advanced Technologies Inc. fell 8.6 percent to $5.93.

Southern First Bancshares Inc. fell 8.5 percent to $8.70.

Performant Financial Corp. fell 8.3 percent to $9.87.

First Federal Bancshares of Arkansas Inc. fell 8.2 percent to $9.86.