user: Question: On what year was the local government area with a surface of 4563 square kilometers established?
Columns: ['Local Government Area', 'Type', 'Major Town', 'Land Area (km²)', 'Pop. 2006', 'Density km −2', 'Towns', 'Est.']
Types: ['text', 'text', 'text', 'text', 'real', 'real', 'real', 'real']
Sample row: ['Roxby Downs', 'Municipal Council', 'Roxby Downs', '110', 4292.0, 39018.0, 2.0, 1982.0]
SQL:

assistant: SELECT "Est." FROM "Table" WHERE "Land Area (km²)" = '4563';