Finite Theory's galactic rotation curve formula applied to various galaxies. The mean standard deviation of all tangential velocities of all stars of all ~ 500 galaxies is only remarkably 8 km/s.
Data taken from:
https://astroweb.cwru.edu/SPARC/MaximumDiskData.mrt https://astroweb.cwru.edu/SPARC/MassModels_Lelli2016c.mrt
https://www.ioa.s.u-tokyo.ac.jp/~sofue/smd2018/
Regards, Fornux Inc.