user: Question: Which Date has a Winning score of 69-68-68-70=275?
Columns: ['Date', 'Tournament', 'Winning score', 'To par', 'Margin of victory']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Sep 16, 1984', 'Greater Milwaukee Open', '67-68-69-68=272', '–16', '5 strokes']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Winning score" = '69-68-68-70=275';