user: Question: How many losingteams were for the cup finaldate 20 August 1989?
Columns: ['Season', 'Cup FinalDate', 'WinningTeam', 'Score', 'LosingTeam', 'Location', 'Cup Final Attendance']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'real']
Sample row: ['1977', '9 October 1977', 'Brisbane City (1)', '1–1 (5-3 Penalties)', 'Marconi Stallions', 'Perry Park , Brisbane (1)', 9000.0]
SQL:

assistant: SELECT COUNT("LosingTeam") FROM "Table" WHERE "Cup FinalDate" = '20 August 1989';