Who many dates are in position 9 and the sellout is 81%?
CREATE TABLE "table1_16331025_2" (
  "dates_mdy" text,
  "position" real,
  "gross_sales" text,
  "tickets_sold_available" text,
  "sellout_pct" text
);
SELECT COUNT("dates_mdy") FROM "table1_16331025_2" WHERE "position"=9 AND "sellout_pct"='81%';