user: ### NOW ANSWER:
Question: What's Bulgaria's lane?
Columns: ['Heat', 'Lane', 'Name', 'Nationality', 'Time']
Types: ['real', 'real', 'text', 'text', 'text']
Sample row: [5.0, 5.0, 'Grant Hackett', 'Australia', '14:38.92']
SQL:

assistant: SELECT AVG("Lane") FROM "Table" WHERE "Nationality" = 'Bulgaria';