user: Question: How many areas (km 2) have 151511 as the census 2006 population?
Columns: ['LGA Name', 'Area (km 2 )', 'Census 2006 population', 'Administrative capital', 'Postal Code']
Types: ['text', 'real', 'real', 'text', 'real']
Sample row: ['Port Harcourt', 109.0, 541115.0, 'Port Harcourt', 500.0]
SQL:

assistant: SELECT COUNT("Area (km 2 )") FROM "Table" WHERE "Census 2006 population" = 151511.0;