CREATE TABLE table_30373 ("Date" TEXT, "Round" TEXT, "Opponent" TEXT, "Result" TEXT, "Venue" TEXT, "Scorers" TEXT, "Attendance" FLOAT, "Match Report" TEXT)

When semi final (2nd leg) is the round what is the highest attendance?
SELECT MAX("Attendance") FROM table_30373 WHERE "Round" = 'Semi Final (2nd leg)'
SELECT MAX("Attendance") FROM "table_30373" WHERE "Round" = 'Semi Final (2nd leg)'