user: Question: What is the average grid for vehicles manufactured by aprilia and having run more than 16 laps?
Columns: ['Rider', 'Manufacturer', 'Laps', 'Time', 'Grid']
Types: ['text', 'text', 'real', 'text', 'real']
Sample row: ['Nicolas Terol', 'Aprilia', 16.0, '29:51.350', 6.0]
SQL:

assistant: SELECT AVG("Grid") FROM "Table" WHERE "Manufacturer" = 'aprilia' AND "Laps" > 16.0;