Summit Therapeutics (SMMT) had the best month in March 2020 by a large-cap US stock in March 2020, returning 66.9%.

ASSET	MONTH	% RETURN
Summit Therapeutics (SMMT)	March 2020	66.9%
BioNTech SE (BNTX)	March 2020	66.81%
Carrier Global (CARR)	March 2020	43.75%
Zoom Video Communications (ZM)	March 2020	33.63%
BJs Wholesale Club (BJ)	March 2020	31.29%
Otis Worldwide (OTIS)	March 2020	25%
Chewy (CHWY)	March 2020	24.97%
Contura Energy (CTRA)	March 2020	22.26%
EQT (EQT)	March 2020	16.67%
Zscaler (ZS)	March 2020	15.24%
Sprouts Farmers Market LLC (SFM)	March 2020	15.11%
Molina Healthcare (MOH)	March 2020	13.14%
ZTO Express (Cayman) (ZTO)	March 2020	12.73%
Hormel Foods (HRL)	March 2020	11.42%
Centene (CNC)	March 2020	11.03%
Moderna (MRNA)	March 2020	10.93%
Veeva Systems Inc Class A (VEEV)	March 2020	9.9%
Regeneron Pharmaceuticals (REGN)	March 2020	9.73%
Take-Two Interactive Software (TTWO)	March 2020	9.24%
ConAgra Foods (CAG)	March 2020	9.23%
Logitech International (LOGI)	March 2020	8.68%
Eli Lilly and (LLY)	March 2020	8.6%
Cloudflare (NET)	March 2020	8.25%
Gilead Sciences (GILD)	March 2020	7.3%
JM Smucker (SJM)	March 2020	7.25%

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