condition mean min max ZT0-3 2.8609216666666666 2.164935 3.28467 ZT4-7 2.427855 2.427855 2.427855 ZT8-11 2.472765 2.472765 2.472765 ZT12-15 4.339617499999999 4.332425 4.34681 ZT16-19 4.086295 4.086295 4.086295 ZT20-23 4.646475 4.646475 4.646475