Axsome Therapeutics (AXSM) had the highest return in March 2019 by a mid-cap US stock or mid-cap US stock, returning 78.5%.

ASSET	MONTH	% RETURN
Axsome Therapeutics (AXSM)	March 2019	78.54%
Catalyst Pharmaceuticals (CPRX)	March 2019	74.06%
Alphatec (ATEC)	March 2019	65.63%
Mercurity Fintech Holding Inc ADR (MFH)	March 2019	59.62%
Protagonist Therapeutics (PTGX)	March 2019	56.54%
Skeena Resources (SKE)	March 2019	43.67%
Krystal Biotech (KRYS)	March 2019	43.11%
Immunitybio (IBRX)	March 2019	38.6%
Soleno Therapeutics (SLNO)	March 2019	36.42%
Acm Research (ACMR)	March 2019	34.17%
Plug Power (PLUG)	March 2019	33.33%
StoneCo (STNE)	March 2019	33.04%
ELF Beauty (ELF)	March 2019	32.5%
Apellis Pharmaceuticals (APLS)	March 2019	27.45%
Merus (MRUS)	March 2019	25.7%
Torm PLC Class A (TRMD)	March 2019	25.21%
YETI (YETI)	March 2019	24.9%
Veracyte (VCYT)	March 2019	23.25%
Rev (REVG)	March 2019	22.76%
Iridium Communications (IRDM)	March 2019	22.35%
Abercrombie & Fitch (ANF)	March 2019	22.23%
CLARIVATE (CLVT)	March 2019	22.18%
TransAlta (TAC)	March 2019	21.32%
TG Therapeutics (TGTX)	March 2019	20.36%
ConAgra Foods (CAG)	March 2019	18.45%

Mid-cap stocks are treated as having a market cap between $2B and $10B.