condition mean min max ZT0-3 4.66772 4.29867 5.031605000000001 ZT4-7 5.209115 5.209115 5.209115 ZT8-11 5.354355 5.354355 5.354355 ZT12-15 7.7722725 7.6073249999999994 7.93722 ZT16-19 6.634655 6.634655 6.634655 ZT20-23 5.394945 5.394945 5.394945