OFG Bancorp (OFG) had the highest return in March 2009 by a small-cap US stock, returning 167.3%.

ASSET	MONTH	% RETURN
OFG Bancorp (OFG)	March 2009	167.33%
Financial Institutions (FISI)	March 2009	131.82%
Green Plains Renewable Energy (GPRE)	March 2009	127.4%
Safehold (SAFE)	March 2009	117.83%
Beazer Homes USA (BZH)	March 2009	102%
Kulicke and Soffa Industries (KLIC)	March 2009	98.48%
Independent Bank (IBCP)	March 2009	90.24%
LSI Industries (LYTS)	March 2009	88%
Hovnanian Enterprises (HOV)	March 2009	83.53%
POET Technologies (POET)	March 2009	83.33%
Telesat (TSAT)	March 2009	82.56%
Digital Turbine (APPS)	March 2009	82%
Helix Energy Solutions (HLX)	March 2009	80.35%
BlueLinx (BXC)	March 2009	76.35%
MBIA (MBI)	March 2009	74.81%
Build-A-Bear Workshop (BBW)	March 2009	73.43%
American Coastal Insurance (ACIC)	March 2009	72.72%
BioCryst Pharmaceuticals (BCRX)	March 2009	72.44%
Sify Technologies (SIFY)	March 2009	71.67%
Canadian Solar (CSIQ)	March 2009	70.86%
Himax Technologies (HIMX)	March 2009	70.73%
G-III Apparel (GIII)	March 2009	64.29%
Dine Brands Global (DIN)	March 2009	63.81%
REX American Resources (REX)	March 2009	63.67%
Northern Dynasty Minerals (NAK)	March 2009	62.59%

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