condition mean min max ZT0-3 0.487035 0.411703 0.562367 ZT4-7 0.206698 0.206698 0.206698 ZT8-11 0.655281 0.655281 0.655281 ZT12-15 1.0365896666666665 0.9257143333333333 1.147465 ZT16-19 0.5785070000000001 0.425049 0.7319650000000001 ZT20-23 0 0 0