user: Question: Between which years were there 241 Fokker 70 model cabins built?
Columns: ['Model', 'Seats', 'Period', 'Built', 'Country']
Types: ['text', 'text', 'text', 'real', 'text']
Sample row: ['Fokker F28 Fellowship', '65-79', '1967-1987', 241.0, 'Netherlands']
SQL:

assistant: SELECT "Period" FROM "Table" WHERE "Built" < 241.0 AND "Model" = 'Fokker 70';