Cytokinetics (CYTK) had the best month in 2004 by a large-cap US stock in April 2004, returning 550.4%.

ASSET	MONTH	% RETURN
Cytokinetics (CYTK)	April 2004	550.39%
QXO (QXO)	March 2004	550%
QXO (QXO)	May 2004	450%
Arrowhead Pharmaceuticals (ARWR)	January 2004	258.97%
Mueller Industries (MLI)	October 2004	133.61%
Cheniere Energy (LNG)	November 2004	128.9%
XPO Logistics (XPO)	January 2004	98.55%
Sterling Construction (STRL)	February 2004	90.08%
Monster Beverage (MNST)	May 2004	89.57%
Arrowhead Pharmaceuticals (ARWR)	December 2004	81.51%
Sterling Construction (STRL)	September 2004	79.71%
Elbit Systems (ESLT)	September 2004	77.71%
Flutter Entertainment (FLUT)	February 2004	77.27%
Axon Enterprise (AXON)	January 2004	61.03%
Alnylam Pharmaceuticals (ALNY)	November 2004	60%
First Majestic Silver (AG)	March 2004	59.82%
IES (IESC)	December 2004	56.63%
Axon Enterprise (AXON)	June 2004	52.97%
Vale SA ADR (VALE)	August 2004	52.69%
Allegheny Technologies (ATI)	June 2004	51.66%
Alphabet Inc Class A (GOOGL)	October 2004	45.75%
Nasdaq (NDAQ)	December 2004	45.72%
MicroStrategy (MSTR)	October 2004	44.36%
ArcelorMittal SA ADR (MT)	August 2004	43.18%
Axon Enterprise (AXON)	March 2004	41.84%

Large-cap stocks are treated as having a market cap of $10B+.