condition mean min max ZT0-3 2.8081199999999997 2.8081199999999997 2.8081199999999997 ZT4-7 2.763065 2.763065 2.763065 ZT8-11 2.998345 2.998345 2.998345 ZT12-15 2.6297949999999997 2.6297949999999997 2.6297949999999997 ZT16-19 3.425695 3.425695 3.425695 ZT20-23 3.931995 3.931995 3.931995