condition mean min max ZT0-3 14.90054 14.90054 14.90054 ZT4-7 68.564873 68.564873 68.564873 ZT8-11 50.646944000000005 50.646944000000005 50.646944000000005 ZT12-15 23.0180905 23.0180905 23.0180905 ZT16-19 22.793369499999997 22.793369499999997 22.793369499999997 ZT20-23 19.507891 19.507891 19.507891