Inventrust Properties (IVT) had the highest return between 2013 and 2014 by a mid-cap US stock, returning 1,067,615%.

ASSET	YEARS	% RETURN
Inventrust Properties (IVT)	2013-2014	1,067,615%
Vipshop (VIPS)	2013-2014	986.12%
Globalstar, Inc Common Stock (GSAT)	2013-2014	759.38%
ANI Pharmaceuticals (ANIP)	2013-2014	651.87%
Catalyst Pharmaceuticals (CPRX)	2013-2014	582.76%
ACADIA Pharmaceuticals (ACAD)	2013-2014	564.23%
Plug Power (PLUG)	2013-2014	500%
Nexstar Broadcasting (NXST)	2013-2014	389.92%
CleanSpark (CLSK)	2013-2014	374.36%
Pilgrims Pride (PPC)	2013-2014	346.12%
Ambarella (AMBA)	2013-2014	323.37%
TG Therapeutics (TGTX)	2013-2014	322.4%
American Airlines (AAL)	2013-2014	292.86%
Agios Pharm (AGIO)	2013-2014	286.34%
Enphase Energy (ENPH)	2013-2014	269.25%
Qorvo (QRVO)	2013-2014	260.65%
Travere Therapeutics (TVTX)	2013-2014	260%
Saia (SAIA)	2013-2014	250.67%
Applied Digital (APLD)	2013-2014	248.28%
Arrowhead Pharmaceuticals (ARWR)	2013-2014	241.67%
MGIC Investment (MTG)	2013-2014	237.68%
RadNet (RDNT)	2013-2014	234.9%
PTC Therapeutics (PTCT)	2013-2014	227.66%
Addus HomeCare (ADUS)	2013-2014	226.21%
Avis Budget (CAR)	2013-2014	224.51%

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