Vertex Pharmaceuticals (VRTX) had the highest return in March 2008 by a US stock in the S&P 500 (GSPC), returning 36.7%.

ASSET	MONTH	% RETURN
Vertex Pharmaceuticals (VRTX)	March 2008	36.67%
Caesars Entertainment (CZR)	March 2008	24.33%
Mastercard (MA)	March 2008	18.42%
Old Dominion Freight Line (ODFL)	March 2008	16.25%
CSX (CSX)	March 2008	15.92%
Intuitive Surgical (ISRG)	March 2008	15.43%
Apple (AAPL)	March 2008	15.31%
Chipotle Mexican Grill (CMG)	March 2008	14.58%
JB Hunt Transport Services (JBHT)	March 2008	14.29%
eBay (EBAY)	March 2008	13.76%
DR Horton (DHI)	March 2008	13.64%
Fastenal (FAST)	March 2008	13.35%
Nike (NKE)	March 2008	13.31%
Steel Dynamics (STLD)	March 2008	13.26%
First Solar (FSLR)	March 2008	13.03%
Amazon (AMZN)	March 2008	12.12%
Discover Financial Services (DFS)	March 2008	11.44%
Johnson Controls International (JCI)	March 2008	11.2%
Tyson Foods (TSN)	March 2008	11.07%
GE Aerospace (GE)	March 2008	11.01%
Expeditors International of Washington (EXPD)	March 2008	10.74%
Analog Devices (ADI)	March 2008	10.71%
NVR (NVR)	March 2008	10.51%
AT&T (T)	March 2008	10.22%
CBRE Group Inc Class A (CBRE)	March 2008	9.79%