Only 3-10 percent of Dutch Cape men had formal recorded interracial relationships

Evidence

Early instances of mixing at the Cape were for obvious reasons relatively small in number. Reliable data are tough to come by, ranging at any one time between roughly 3 and 10 percent of European men for whom formal relationships with local (usually Khoisan) or imported women of color were recorded, strongly suggesting (as I must keep insisting) a larger number of unrecorded relationships. — David Theo Goldberg, The Threat of Race, 1328

Categorization

• QUESTION: What does ‘formal relationships’ cover, and how would unrecorded mixing skew the real proportion?