How many numbers were recorded under 2001 when 2006 was 18.9?
CREATE TABLE "table1_18660332_2" (
  "ethnic_group" text,
  "2001_pct" text,
  "2001_people" text,
  "2006_pct" text,
  "2006_people" real
);
SELECT COUNT("2001_pct") FROM "table1_18660332_2" WHERE "2006_pct"='18.9';