Vera Therapeutics (VERA) had the highest return in January 2010 by a mid-cap US stock, returning 80%.

ASSET	MONTH	% RETURN
Vera Therapeutics (VERA)	January 2010	80%
Zions Bancorporation (ZION)	January 2010	46.71%
Sirius XM (SIRI)	January 2010	37.71%
Caesars Entertainment (CZR)	January 2010	34.92%
Western Alliance Bancorporation (WAL)	January 2010	31.88%
United Community Banks (UCB)	January 2010	30.52%
Ameris Bancorp (ABCB)	January 2010	27.77%
Cathay General Bancorp (CATY)	January 2010	25.23%
Crocs (CROX)	January 2010	25.21%
Credit Acceptance (CACC)	January 2010	24.26%
Banc of California (BANC)	January 2010	23.92%
United Bankshares (UBSI)	January 2010	21.88%
Genworth Financial (GNW)	January 2010	19.1%
Enterprise Financial Services (EFSC)	January 2010	18.83%
Sanmina (SANM)	January 2010	18.71%
Texas Capital Bancshares (TCBI)	January 2010	18.66%
Axos Financial (AX)	January 2010	18.6%
Avadel Pharmaceuticals (AVDL)	January 2010	18.28%
Plexus (PLXS)	January 2010	17.56%
MGM Resorts International (MGM)	January 2010	17.29%
Jazz Pharmaceuticals (JAZZ)	January 2010	16.63%
Columbia Banking System (COLB)	January 2010	16.58%
WesBanco (WSBC)	January 2010	16.55%
Liberty Global PLC Class B (LBTYB)	January 2010	16.26%
Quantum Computing (QUBT)	January 2010	15.79%

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