West Pharmaceutical Services (WST) had the highest return on April 17, 2012 by a US stock in the S&P 500 (GSPC), returning 7.3%.

ASSET	DATE	% RETURN
West Pharmaceutical Services (WST)	4/17/2012	7.26%
First Solar (FSLR)	4/17/2012	6.15%
Apple (AAPL)	4/17/2012	5.31%
Netflix (NFLX)	4/17/2012	5.23%
Walgreens Boots Alliance (WBA)	4/17/2012	5.13%
Builders FirstSource (BLDR)	4/17/2012	4.76%
Deckers Outdoor (DECK)	4/17/2012	4.67%
Laboratory Corporation of America (LH)	4/17/2012	3.55%
Edwards Lifesciences (EW)	4/17/2012	3.43%
Juniper Networks (JNPR)	4/17/2012	3.4%
Trimble (TRMB)	4/17/2012	2.99%
Accenture (ACN)	4/17/2012	2.87%
FactSet Research Systems (FDS)	4/17/2012	2.69%
Universal Health Services (UHS)	4/17/2012	2.69%
VeriSign (VRSN)	4/17/2012	2.65%
Quest Diagnostics (DGX)	4/17/2012	2.6%
Caesars Entertainment (CZR)	4/17/2012	2.6%
Teradyne (TER)	4/17/2012	2.56%
TJX Companies (TJX)	4/17/2012	2.55%
Take-Two Interactive Software (TTWO)	4/17/2012	2.52%
Align Technology (ALGN)	4/17/2012	2.5%
Cardinal Health (CAH)	4/17/2012	2.43%
Axon Enterprise (AXON)	4/17/2012	2.43%
W R Berkley (WRB)	4/17/2012	2.41%
Molina Healthcare (MOH)	4/17/2012	2.38%