condition mean min max ZT0-3 0.7461796666666667 0.3484155 0.9760260000000001 ZT4-7 0.574959 0.574959 0.574959 ZT8-11 0.998938 0.998938 0.998938 ZT12-15 1.5714650000000001 1.5430000000000001 1.59993 ZT16-19 1.18316 1.18316 1.18316 ZT20-23 1.005025 1.005025 1.005025