user: Question: Tell me the average Laps for grid larger than 12 and bikes of Ducati 999RS for Dean Ellison
Columns: ['Rider', 'Bike', 'Laps', 'Time', 'Grid']
Types: ['text', 'text', 'real', 'text', 'real']
Sample row: ['Noriyuki Haga', 'Yamaha YZF-R1', 23.0, '35:26.734', 2.0]
SQL:

assistant: SELECT AVG("Laps") FROM "Table" WHERE "Grid" > 12.0 AND "Bike" = 'Ducati 999RS' AND "Rider" = 'Dean Ellison';