condition mean min max ZT0-3 30.1477 30.1477 30.1477 ZT4-7 19.8186 19.8186 19.8186 ZT8-11 40.4677 40.4677 40.4677 ZT12-15 23.48865 23.48865 23.48865 ZT16-19 52.122749999999996 52.122749999999996 52.122749999999996 ZT20-23 40.97975 40.97975 40.97975