user: Question: How many titles have U.S. viewers 1.66 million.
Columns: ['No. in series', 'No. in season', 'Title', 'Directed by', 'Written by', 'Original air date', 'U.S. viewers (millions)']
Types: ['real', 'real', 'text', 'text', 'text', 'text', 'text']
Sample row: [8.0, 1.0, '"Seven Thirty-Seven"', 'Bryan Cranston', 'J. Roberts', 'March8,2009', '1.66']
SQL:

assistant: SELECT COUNT("Title") FROM "Table" WHERE "U.S. viewers (millions)" = '1.66';