condition mean min max ZT0-3 4.536905 4.536905 4.536905 ZT4-7 2.53484 2.53484 2.53484 ZT8-11 4.298344999999999 4.298344999999999 4.298344999999999 ZT12-15 10.729225 10.729225 10.729225 ZT16-19 10.035910000000001 10.035910000000001 10.035910000000001 ZT20-23 7.889075 7.889075 7.889075