The 96% number refers to the orange fuel tank. Once you factor in the shuttle, the payload, and rocket engines, it's more like... 94% fuel. Some rockets are 88%

The 96% number refers to the orange fuel tank. Once you factor in the shuttle, the payload, and rocket engines, it's more like... 94% fuel. Some rockets are 88% fuel, but still only ~2-3% payload. A lighter rocket could mean 10% payload.