How are Yamato TA-Q-BIN parcel sizes determined?

TA-Q-BIN sizes run from Size 60 to Size 200, where the number is the sum of the parcel's length, width, and height in centimeters, up to 200 cm and 30 kg. The size is set by the larger of the dimension total or the weight. For example, a box totaling 70 cm but weighing 9 kg is charged as Size 100.