condition mean min max ZT0-3 0.8728903333333333 0.229009 1.4415955 ZT4-7 1.0370534999999999 1.0370534999999999 1.0370534999999999 ZT8-11 0.707362 0.707362 0.707362 ZT12-15 1.150177 0.9340685 1.3662855 ZT16-19 1.567105 1.567105 1.567105 ZT20-23 2.406035 2.406035 2.406035