Neonode (NEON) had the highest return in April 2020 by a small-cap US stock, returning 216.3%.

ASSET	MONTH	% RETURN
Neonode (NEON)	April 2020	216.27%
Vital Energy (VTLE)	April 2020	186.84%
Bit Digital (BTBT)	April 2020	174.07%
Beyond (BYON)	April 2020	166.24%
NGL Energy Partners (NGL)	April 2020	156.35%
Arcturus Therapeutics (ARCT)	April 2020	153.49%
SandRidge Energy (SD)	April 2020	123.59%
HIVE Blockchain Technologies (HIVE)	April 2020	108.65%
Domo (DOMO)	April 2020	107.36%
Microvision (MVIS)	April 2020	105.88%
Talos Energy (TALO)	April 2020	102.31%
BioCryst Pharmaceuticals (BCRX)	April 2020	100.51%
Aquestive Therapeutics (AQST)	April 2020	100.47%
Core Laboratories (CLB)	April 2020	96.69%
Kosmos Energy (KOS)	April 2020	96.43%
Ellington Financial (EFC)	April 2020	95.7%
Alpha and Omega Semiconductor (AOSL)	April 2020	93.72%
Arcus Biosciences (RCUS)	April 2020	91.38%
Liberty Oilfield Services (LBRT)	April 2020	90.33%
Know Labs (KNW)	April 2020	89.37%
Amarin (AMRN)	April 2020	89.3%
Replimune (REPL)	April 2020	88.63%
Build-A-Bear Workshop (BBW)	April 2020	86.76%
Calumet Specialty Products Partners (CLMT)	April 2020	84.76%
ProPetro (PUMP)	April 2020	84.35%

Small-cap stocks are treated as having a market cap between $300M and $2B.