user: Question: What was the chassis of Emilio de Villota in 1981?
Columns: ['Year', 'Entrant', 'Chassis', 'Engine', 'Points']
Types: ['real', 'text', 'text', 'text', 'real']
Sample row: [1976.0, 'RAM Racing', 'Brabham BT44B', 'Cosworth V8', 0.0]
SQL:

assistant: SELECT "Chassis" FROM "Table" WHERE "Year" > 1981.0;