condition mean min max ZT0-3 394.385903 394.385903 394.385903 ZT4-7 304.041988 304.041988 304.041988 ZT8-11 335.47593400000005 335.47593400000005 335.47593400000005 ZT12-15 309.81746599999997 309.81746599999997 309.81746599999997 ZT16-19 400.0393845 400.0393845 400.0393845 ZT20-23 390.8700245 390.8700245 390.8700245