SoundHound AI (SOUN) had the best day in December 2022 by a mid-cap US stock on December 30, 2022, returning 75.2%.

ASSET	DATE	% RETURN
SoundHound AI (SOUN)	12/30/2022	75.25%
Soleno Therapeutics (SLNO)	12/19/2022	66.67%
Viking Therapeutics (VKTX)	12/19/2022	28.26%
Spyre Therapeutics (SYRE)	12/30/2022	26.76%
Terawulf (WULF)	12/23/2022	26.23%
Soleno Therapeutics (SLNO)	12/27/2022	26.17%
Eos Energy Enterprises (EOSE)	12/30/2022	25.42%
Cipher Mining (CIFR)	12/30/2022	24.44%
Wave Life Sciences (WVE)	12/14/2022	24.12%
NewAmsterdam Pharma Company NV Ordinary Shares (NAMS)	12/15/2022	23.84%
Celcuity LLC (CELC)	12/8/2022	23.1%
Terawulf (WULF)	12/12/2022	21.21%
Ivanhoe Electric (IE)	12/16/2022	21.18%
Terawulf (WULF)	12/8/2022	21.18%
Celcuity LLC (CELC)	12/19/2022	20.24%
TAL Education (TAL)	12/20/2022	19.61%
Rhythm Pharmaceuticals (RYTM)	12/12/2022	18.7%
Galaxy Digital (GLXY)	12/29/2022	18.31%
Immunome (IMNM)	12/20/2022	18.3%
Cidara Therapeutics (CDTX)	12/22/2022	17.92%
Cidara Therapeutics (CDTX)	12/29/2022	17.78%
Cipher Mining (CIFR)	12/2/2022	17.28%
TMC the metals (TMC)	12/29/2022	17.1%
Kingsoft Cloud Holdings (KC)	12/2/2022	16.84%
RLX Technology (RLX)	12/2/2022	16.52%

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