condition mean min max ZT0-3 16.669583333333335 14.397549999999999 18.780900000000003 ZT4-7 11.738900000000001 11.738900000000001 11.738900000000001 ZT8-11 14.2196 14.2196 14.2196 ZT12-15 20.604 19.17085 22.037149999999997 ZT16-19 19.284750000000003 19.284750000000003 19.284750000000003 ZT20-23 22.23145 22.23145 22.23145