condition mean min max ZT0-3 7.666365 6.549785 9.722155 ZT4-7 6.054195 6.054195 6.054195 ZT8-11 7.239775 7.239775 7.239775 ZT12-15 9.96968 9.42331 10.51605 ZT16-19 10.093 10.093 10.093 ZT20-23 9.954325 9.954325 9.954325