condition mean min max ZT0-3 3.801325 2.550275 5.36106 ZT4-7 4.37019 4.37019 4.37019 ZT8-11 5.605645 5.605645 5.605645 ZT12-15 9.18873 8.866085 9.511375000000001 ZT16-19 6.426155 6.426155 6.426155 ZT20-23 5.115855 5.115855 5.115855