user: Question: What is the Area of the allardville Parish with a Population smaller than 2151?
Columns: ['Official Name', 'Status', 'Area km 2', 'Population', 'Census Ranking']
Types: ['text', 'text', 'real', 'real', 'text']
Sample row: ['Saumarez', 'Parish', 326.76, 6837.0, '528 of 5,008']
SQL:

assistant: SELECT "Area km 2" FROM "Table" WHERE "Official Name" = 'allardville' AND "Population" < 2151.0;