Bank of China Tower
The John Hancock Center was far more efficient than earlier steel-frame structures. Where the Empire State Building (1931), required about 206 kilograms of steel per square metre and 28 Liberty Street (1961) required 275, the John Hancock Center required only 145. The trussed tube concept was applied to many later skyscrapers, including the Onterie Center, Citigroup Center and Bank of China Tower.