condition mean min max ZT0-3 4.3214375 4.186904999999999 4.455970000000001 ZT4-7 7.40775 7.40775 7.40775 ZT8-11 11.915665 11.915665 11.915665 ZT12-15 0 0 0 ZT16-19 5.21694 5.21694 5.21694 ZT20-23 3.8057300000000005 3.8057300000000005 3.8057300000000005