The NYSE Arca Disk Drive Index (DDX) - Quarterly Rebalancing			
"Changes effective before the open of trading Monday, August 19, 2013"			
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Symbol	Component Name	Previous Share Weight	Rebalanced Share Weight
EMC	EMC Corp	13387	14200
FIO	Fusion-io Inc	21941	34218
IMN	Imation Corp	84068	80065
NTAP	NetApp Inc	8576	8709
OCZ	OCZ Technology Group Inc	275001	255208
QTM	Quantum Corp	226924	243377
SNDK	SanDisk Corp	5417	6585
STEC	STEC Inc	95723	54044
STX	Seagate Technology PLC	7825	9382
WDC	Western Digital Corp	5367	5689