condition mean min max ZT0-3 1.1469211666666665 0.686688 1.620175 ZT4-7 0.8948415 0.8948415 0.8948415 ZT8-11 1.1678264999999999 1.1678264999999999 1.1678264999999999 ZT12-15 2.67222 2.4501999999999997 2.89424 ZT16-19 3.099455 3.099455 3.099455 ZT20-23 3.0911150000000003 3.0911150000000003 3.0911150000000003