Seems you have more detailed info. I just checked full-load efficiencies of transformers and it turned out to vary from 95% to 98.5% and the comprehensive effic

Seems you have more detailed info. I just checked full-load efficiencies of transformers and it turned out to vary from 95% to 98.5% and the comprehensive efficiency can actually drop below 90%. If we factor in the loss on wires, I guess my estimate of loss per transformer layer 10% should be pretty close to actual. So I'm not surprised to see a transmission loss of 50% to 60%.