condition mean min max ZT0-3 31.894775 30.44245 33.3471 ZT4-7 29.8988 29.8988 29.8988 ZT8-11 37.2299 37.2299 37.2299 ZT12-15 0 0 0 ZT16-19 41.11325 41.11325 41.11325 ZT20-23 35.64425 35.64425 35.64425