user: Question: What was the attendance on May 21?
Columns: ['Date', 'Opponent', 'Score', 'Loss', 'Attendance', 'Series', 'Arena']
Types: ['text', 'text', 'text', 'text', 'real', 'text', 'text']
Sample row: ['May 19', 'Oilers', '3–1', 'Bryzgalov (6–2)', 17174.0, '0–1', 'Arrowhead Pond of Anaheim']
SQL:

assistant: SELECT "Attendance" FROM "Table" WHERE "Date" = 'May 21';