condition mean min max ZT0-3 16.623912455 11.78716837 21.46065654 ZT4-7 21.5804455225 19.636687115 23.52420393 ZT8-11 20.7989957725 20.30854802 21.289443525 ZT12-15 12.72826351525 11.467321525 13.9892055055 ZT16-19 13.2592958825 13.09444665 13.424145115 ZT20-23 16.3720863925 15.15452033 17.589652455