Advanced Micro Devices (AMD) had the highest return between 2015 and 2019 by a mega-cap US stock, returning 1,617.6%.

ASSET	YEARS	% RETURN
Advanced Micro Devices (AMD)	2015-2019	1,617.6%
NVIDIA (NVDA)	2015-2019	1,112.43%
Netflix (NFLX)	2015-2019	558.3%
Amazon (AMZN)	2015-2019	491.16%
Lam Research (LRCX)	2015-2019	298.23%
Microsoft (MSFT)	2015-2019	276.47%
Mastercard (MA)	2015-2019	256.24%
Broadcom (AVGO)	2015-2019	251.66%
Arista Networks (ANET)	2015-2019	234.76%
UnitedHealth (UNH)	2015-2019	213.32%
Taiwan Semiconductor Manufacturing (TSM)	2015-2019	204.16%
Visa Inc Class A (V)	2015-2019	195.43%
KLA (KLAC)	2015-2019	190.16%
ASML Holding NV New York Registry Shares (ASML)	2015-2019	190.1%
Apple (AAPL)	2015-2019	186.92%
Texas Instruments (TXN)	2015-2019	172.9%
Applied Materials (AMAT)	2015-2019	164.68%
Thermo Fisher Scientific (TMO)	2015-2019	161.84%
Facebook (META)	2015-2019	161.2%
JPMorgan Chase (JPM)	2015-2019	154.13%
Alphabet Inc Class C (GOOG)	2015-2019	153.43%
Alphabet Inc Class A (GOOGL)	2015-2019	151.48%
Costco Wholesale (COST)	2015-2019	135.01%
Home Depot (HD)	2015-2019	132.53%
Eli Lilly and (LLY)	2015-2019	113.62%

Mega-cap stocks are treated as having a market cap of $200B+.