user: Question: What was the tie number when Peterborough United was the away team?
Columns: ['Tie no', 'Home team', 'Score', 'Away team', 'Date']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['1', 'Derby County', '0–1', 'Leeds United', '18 February 1975']
SQL:

assistant: SELECT COUNT("Tie no") FROM "Table" WHERE "Away team" = 'Peterborough United';