condition mean min max ZT0-3 34.1965 34.1965 34.1965 ZT4-7 23.3925 23.3925 23.3925 ZT8-11 19.723399999999998 19.723399999999998 19.723399999999998 ZT12-15 20.384050000000002 20.384050000000002 20.384050000000002 ZT16-19 28.7793 28.7793 28.7793 ZT20-23 31.9653 31.9653 31.9653