user: Question: What was the series score when St. Louis was away on April 18?
Columns: ['Date', 'Visitor', 'Score', 'Home', 'Decision', 'Attendance', 'Series']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: ['April 4', 'St. Louis', '1 – 0', 'Philadelphia', 'Hall', 10649.0, 'Blues lead 1–0']
SQL:

assistant: SELECT "Series" FROM "Table" WHERE "Visitor" = 'St. Louis' AND "Date" = 'April 18';