user: Question: How many times was the background Self-employed - media agency?
Columns: ['Candidate', 'Background', 'Original team', 'Age', 'Hometown', 'Result']
Types: ['text', 'text', 'text', 'real', 'text', 'text']
Sample row: ['Thomas Ben', 'Divisional Manager', 'Number 8', 34.0, 'Auckland', 'Hired by Serepisos']
SQL:

assistant: SELECT COUNT("Candidate") FROM "Table" WHERE "Background" = 'Self-employed - media agency';