** Shares of CarMax KMX.N fall ~7% to about $45.70 in premarket trading
** KMX reports Q4 adjusted EPS of 34 cents, down from 64 cents a year ago
** Says gross profit per retail used unit fell $207 from last year, reflecting pricing actions aimed at improving sales trends
** Quarterly revenue came in at $5.95 bln vs 6 bln a year earlier
** Co says quarterly results hit by per-share charges of 99 cents related to a non-cash goodwill impairment and 20 cents tied to restructuring
** As of last close, shares up about 27% YTD
(Reporting by Parth Chandna)
((Parth.Chandna@thomsonreuters.com;))