user: Question: Tyne and Wear County has what total membership for their metropolitan area?
Columns: ['City', 'County', 'Region', 'Local authority', 'Type', 'Population', 'Urban area', 'Metropolitan area']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'real', 'real']
Sample row: ['Birmingham', 'West Midlands', 'West Midlands', 'Birmingham City Council', 'Metropolitan borough', 1073000.0, 2284093.0, 3683000.0]
SQL:

assistant: SELECT SUM("Metropolitan area") FROM "Table" WHERE "County" = 'Tyne and Wear';