condition mean min max ZT0-3 8.540268 8.540268 8.540268 ZT4-7 9.845648 9.845648 9.845648 ZT8-11 9.856987499999999 9.856987499999999 9.856987499999999 ZT12-15 9.309491000000001 9.309491000000001 9.309491000000001 ZT16-19 8.3493275 8.3493275 8.3493275 ZT20-23 8.57246 8.57246 8.57246