condition mean min max ZT0-3 14.58475 13.40545 15.764050000000001 ZT4-7 19.5047 19.5047 19.5047 ZT8-11 26.042450000000002 26.042450000000002 26.042450000000002 ZT12-15 0 0 0 ZT16-19 26.936149999999998 26.936149999999998 26.936149999999998 ZT20-23 23.2375 23.2375 23.2375