A 25-year-old man was fatally shot in the back outside a Bronx apartment building, cops said Sunday. The victim was shot on E. 233rd St. near White Plains Road in Wakefield about 10:35 p.m. Saturday, cops said. Medics rushed the man to Jacobi Medical Center but he could not be saved. His name was not immediately released. No arrests have been made. The killing comes amid a drop in murders this year in the Bronx’s 47th Precinct, which has seen six homicides and 22 shootings through Nov. 17, compared to 10 slayings and 31 shootings in the same timeframe last year.