Qorvo (QRVO) had the highest return in July 1998 by a large-cap US stock, returning 58.6%.

ASSET	MONTH	% RETURN
Qorvo (QRVO)	July 1998	58.62%
SK Telecom Co Ltd ADR (SKM)	July 1998	34.78%
Cognizant Technology Solutions Corp Class A (CTSH)	July 1998	33.3%
Micron Technology (MU)	July 1998	31.93%
MicroStrategy (MSTR)	July 1998	27.71%
ICON (ICLR)	July 1998	25.63%
Best Buy (BBY)	July 1998	25.08%
Monster Beverage (MNST)	July 1998	23.89%
Korea Electric Power Corp ADR (KEP)	July 1998	20.51%
Apple (AAPL)	July 1998	19.92%
SEI Investments (SEIC)	July 1998	19.9%
CoStar (CSGP)	July 1998	19.44%
Nokia (NOK)	July 1998	17.51%
Paramount Skydance Corporation Class B Common Stock (PSKY)	July 1998	17.1%
Jack Henry & Associates (JKHY)	July 1998	15.48%
Suzano Papel e Celulose SA ADR (SUZ)	July 1998	15.39%
Match (MTCH)	July 1998	15.27%
CoreSite Realty (COR)	July 1998	14.91%
Invesco (IVZ)	July 1998	14.71%
Celestica (CLS)	July 1998	14.52%
International Business Machines (IBM)	July 1998	14.22%
Cheniere Energy (LNG)	July 1998	14.16%
ING Group NV ADR (ING)	July 1998	13.23%
Intel (INTC)	July 1998	13.05%
Comcast (CMCSA)	July 1998	12.95%

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