26 COOPER v. HARRIS Opinion of the Court to use race” in designing District 12, Hofeller added a qualification: “except perhaps with regard to Guilford County.” Id., at 2791; see id., at 2790. As the District Court understood, that is the kind of “exception” that goes pretty far toward swallowing the rule. District 12 saw a net increase of more than 25,000 black voters in Guilford County, relative to a net gain of fewer than 35,000 across the district: So the newly added parts of that county played a major role in pushing the district’s BVAP over 50%. See id., at 384, 500–502.13 The District Court came away from Hofeller’s self-contradictory testimony unpersuaded that this decisive influx of black voters was an accident. Whether the racial make-up of the county was displayed on his computer screen or just fixed in his head, the court thought, Hofeller’s denial of race-based districting “r[ang] hollow.” 159 F. Supp. 3d, at 620, n. 8. Finally, an expert report by Dr. Stephen Ansolabehere lent circumstantial support to the plaintiffs’ race-notpolitics case. Ansolabehere looked at the six counties overlapping with District 12—essentially the region from which the mapmakers could have drawn the district’s population. The question he asked was: Who from those counties actually ended up in District 12? The answer he found was: Only 16% of the region’s white registered voters, but 64% of the black ones. See App. 321–322. Ansolabehere next controlled for party registration, but —————— 13 The dissent charges that this comparison is misleading, but offers no good reason why that is so. See post, at 29–30. It is quite true, as the dissent notes, that another part of District 12 (in Mecklenburg County) experienced a net increase in black voters even larger than the one in Guilford County. See post, at 30. (The net increases in the two counties thus totaled more than 35,000; they were then partially offset by net decreases in other counties in District 12.) But that is irrelevant to the point made here: Without the numerous black voters added to District 12 in Guilford County—where the evidence most clearly indicates voters were chosen based on race—the district would have fallen well shy of majority-minority status.