user: Question: When were the shares 39.1%?
Columns: ['Show', 'Date', 'Official ratings (millions)', 'Weekly rank', 'Share']
Types: ['text', 'text', 'real', 'text', 'text']
Sample row: ['Auditions 1', '12 April', 9.44, '6', '37.0%']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Share" = '39.1%';