CREATE TABLE "round_9" (
  "home_team" text,
  "home_team_score" text,
  "away_team" text,
  "away_team_score" text,
  "venue" text,
  "crowd" real,
  "date" text
);

Question: What was the smallest crowd at a home game of carlton?
SQL: SELECT MIN("crowd") FROM "round_9" WHERE "home_team"='carlton';