In an piece for The Monkey Cage, Bernard Fraga, present new estimates from Catalist of changes in turnout by race from 2012 to 2016.
Nationally, African-American turnout declined by 4.7%. In contrast, white turnout was up 2.4%, Asian-American turnout increased by 3.0%, and Latino turnout rose by 3.8%. In Maryland, white turnout rates increased by 1.8%, while black turnout fell by 3.3%. Data for other groups were unavailable.
The blog post suggests that Clinton might have won if she had been able to keep black turnout as high as 2012 by taking Michigan, Pennsylvania and Wisconsin, albeit the latter two by razor thin margins. Of course, it was never likely that she would inspire as high an African-American turnout as the first black president.