user: Question: In 1950 what is the average rank?
Columns: ['Rank', 'Name', 'Street Address', 'Height feet / m', 'Floors', 'Year']
Types: ['real', 'text', 'text', 'text', 'real', 'real']
Sample row: [1.0, 'Bank of America Tower', '50 North Laura Street', '617 / 188', 42.0, 1990.0]
SQL:

assistant: SELECT AVG("Rank") FROM "Table" WHERE "Year" = 1950.0;