user: Question: Can you tell me the average Attendance that has the Scorers of Steven, Johnston, Walters, McCoist, I.Ferguson?
Columns: ['Date', 'Opponent', 'Venue', 'Result', 'Attendance', 'Scorers']
Types: ['text', 'text', 'text', 'text', 'real', 'text']
Sample row: ['15 August 1989', 'Arbroath', 'H', '4–0', 31762.0, 'McCoist (3), I.Ferguson']
SQL:

assistant: SELECT AVG("Attendance") FROM "Table" WHERE "Scorers" = 'Steven, Johnston, Walters, McCoist, I.Ferguson';