condition mean min max ZT0-3 29.023725 24.5111 33.53635 ZT4-7 10.6954 10.6954 10.6954 ZT8-11 5.674055 5.674055 5.674055 ZT12-15 0 0 0 ZT16-19 7.740715 7.740715 7.740715 ZT20-23 13.66445 13.66445 13.66445